bluuebunny/crossref_metadata_2025 huggingface dataset:
Sense organs on the antennal flagellum of a praying mantis, Tenodera angustipennis, and of two related species (Mantodea)
Authors: Slifer Eleanor H.
Published: February 2005

About 10,000 sense organs are present on one antenna of a female mantis, Tenodera angustipennis, and nearly 40,000 on that of a male. These are of four kinds: (1) thick‐walled pegs, (2) short thin‐walled pegs, (3) medium length thin‐walled pegs and (4) long thin‐walled pegs. All have the structural characteristics of chemoreceptors. The dendrites of the sensory neurons of the thick‐walled pegs are exposed to the air in an opening at its distal end and those of the thin‐walled pegs terminate at many pores in the surface. The significance of the larger number of sense organs possessed by the male is discussed. No important differences were found between the antenna of Tenodera angustipennis and those of T. aridifolia and T. australasiae.
The fine structure of the Limulus optic nerve
Authors: Nunnemacher Rudolph F. , Davis Patricia P.
Published: February 2005

Two complete composite photographs of the optic nerve of Limulus, made by electron microscopy, reveal the presence of neurosecretory granules in the large axons of the rudimentary eye neurons. The number of intermediate sized, (3–7 μ), of eccentric cells corresponds with the number of ommatidia as expected, but only their sheath of Schwann cells show an intimate interfolding. Based on the number of fine axons within the nerve each ommatidium has an average of 12–13 retinular cells. The diameter of their fibers is between 0.2 and 3 μ although the majority are between 1 and 1.5 μ. They are aggregated into bundles of six to seven fibers by the sheath cells although some bundles contain only two, others as many as 181 fibers. There is no indication in these studies that retinular cell axons within a bundle are associated with the same, adjacent, or other pattern of ommatidia. The photographs suggest that physiological activity in retinular cell axons might be detected most easily in the smallest bundles because they contain the fewest, but the larger retinular cell axons.
Adaptive problems and possibilities in the temporal fenestration of tetrapod skulls
Authors: Frazzetta T. H.
Published: February 2005

Adaptive explanations for the temporal fenestration in reptiles are briefly reviewed. With few possible exceptions, fenestrate appeared first in the reptiles, and have seemingly evolved independently in several different phyletic lines.

The several explanations for fenestration offered by previous authors include speculations that open spaces in the skull permitted bulging of the jaw‐closing muscles, and that fenestrae formed in areas of reduced stress where the presence of bone would be functionally useless. The first of these does not readily apply to initial evolutionary stages; the second is more satisfactory.

Certain features of muscular attachments to bones are dealt with, and their implications applied to the fenestration problem to add another possible explanation (which need not contradict previously published suggestions).

Considerations of cranial strength in tetrapod skulls led to speculations on the lack of fenestration in temnospondyls, anthracosaurs, microsaurs and cotylosaurs.

Emargination of the skull roof in turtles is also discussed.
Sense organs on the antennal flagellum of a giant cockroach, Gromphadorhina portentosa, and a comparison with those of several other species (Dictyoptera, Blattaria)
Authors: Slifer Eleanor H.
Published: February 2005

Two kinds of tactile hairs, plain and wavy, thick‐walled chemoreceptors and two types of thin‐walled chemoreceptors are present on the antennal flagellum of Gromphadorhina portentosa males. These are described and their location on the antenna noted. Females of this species have plain tactile hairs and the same types of chemoreceptors as do the males but wavy tactile hairs are absent. The antennal sense organs of a few specimens of five other species of cockroaches — Periplaneta americana, Blatta orientalis, Supella longipalpa, Pycnoscelus surinamensis and Diploptera punctata — were also examined. All lacked tactile hairs but were provided with thick‐walled chemoreceptors and with two types of thin‐walled chemoreceptors similar to those described for Gromphadorhina portentosa.
Morphology of the larval and adult brains of the monarch butterfly, Danaus plexippus plexippus, L.
Authors: Nordlander Ruth H. , Edwards John S.
Published: February 2005

Cell population and neuropile morphology of larval and adult brains of the monarch butterfly, Danaus plexippus plexippus, L., are compared. The larval brain is in continuous transition, the processes of adult brain development being underway from the earliest larval stages. It is characterized by a less diverse population of cells and more homogenous fiber areas than those of the adult. Neuroblasts, which divide to form the neurones of the adult brain, occur either in discrete proliferation centers or scattered among the larval ganglion cells. The larval brain contains, in addition to small homogeneous antennal centers and a distinct larval optic center, rapidly developing adult optic centers, corpora pedunculata, and protocerebral bridge. The larval brain lacks a central body. Major differences between larval and adult brains are clearly related to the increased dependence of the adult upon sensory input from the eyes and antennae.
Development of the oocyte and its accessory cells of the polychaete, Diopatra cuprea (Bosc)
Authors: Anderson Everett , Huebner Erwin
Published: February 2005

The oocyte‐nurse cell complex of the polychaetous annelid, Diopatra cuprea, has been explored by various methods of light microscopy and by the technique of electron microscopy. Early in its development the complex appears as a string of cells floating within the coelomic cavity. As this string of cells develops, the volume of one cell (approximately the middle one) increases greatly; while that of the remaining cells, referred to as nurse cells, increase slightly. Due to this differential growth, the two opposing strands of nurse cells are displaced to one side of the oocyte.

Nurse cells are joined to one another by cytoplasmic bridges. Cytoplasmic bridges also exist between the strands of nurse cells and the oocyte. The presence of numerous ribosomes within the bridges between the oocyte and nurse cells encourages us to suggest that this organelle may be transferred to the oocyte via this route. The transported ribosomes may be used by the maturing oocyte, or they may be stored by the egg to be utilized during embryogenesis. Moreover, we believe that the nurse cells are not involved in the production of the protein‐carbohydrate yolk bodies for we think that these are elaborated by the endoplasmic reticulum in collaboration with certain Golgi complexes of the oocyte.
Limb regeneration and survival of prolactin treated hypophysectomized adult newts
Authors: Connelly Thomas G. , Tassava Roy A. , Thornton Charles S.
Published: February 2005

Hypophysectomized adult newts exhibited 98% survival and limb regeneration at 23 days post‐hypophysectomy when injected intraperitoneally every other day with prolactin (0.015 U/newt) and kept continuously in aquaria with 1 × 10−7 concentration of thyroxine. Thyroxine alone was no more effective than saline injections.

Prolactin (1.2 U/newt every other day) alone increased survival and limb regeneration, but less effectively than did the prolactin‐thyroxine combination.
Tooth attachment by means of a periodontium in the trigger‐fish (Balistidae)
Authors: Soule John D.
Published: February 2005

Tooth attachment in the majority of the bony fish is by ankylosis or fibrous membrane. However, in one group of the osteichthys, the trigger‐fish or balistids, tooth attachment is by means of a periodontium composed of a shallow alveolar socket, a periodontal ligament and acellular cementum.

Histologically, the balistid periodontal ligament is composed of a dense fibro‐cellular connective tissue possessing an abundance of typical fibrocytes, collagen fiber bundles, and oxytalan fibers. The collagen fiber bundles which resemble the principal fiber bundles of the mammalian periodontal ligament are inserted into the bone of the shallow alveolar sockets and are anchored to the teeth by means of a layer of amorphous acellular cementum that covers the radicular dentin. No cementoblasts were found in functional teeth, and epithelial rests are lacking. The mid‐central zone of the balistid periodontal ligament is occupied by small blood vessels.
Innervation of the antennal musculature of the centipede Scolopendra morsitans Linn.
Authors: Changulani Veena
Published: February 2005

A detailed description of the innervation of the individual muscles of the antenna of the centipede Scolopendra morsitans is given. There are six nerves supplying the antennal muscles of each side. The nerve N I consists of 26 bundles of which two are motor, 12 sensory and 12 are mixed. It innervates the intrinsic muscles of the antenna and the antennal sense organs. The nerves N II, N III and N IV innervate the dorsal extrinsic muscles and the nerve N V and N VI the ventral extrinsic muscles.
On the mechanism of respiration in the bullfrog, Rana catesbeiana: A reassessment
Authors: De Jongh H. J. , Gans Carl
Published: February 2005

The mechanism of respiration in the bullfrog has been analyzed by means of pressure recordings from the buccal cavity, the lungs and the abdominal cavity, by cinematography and cinefluorography, and by electromyography of buccal, laryngeal and abdominal muscles. Gas flow was investigated by putting frogs in atmospheres of changing argon and nitrogen content and monitoring the concentration of the nostril efflux.

Three kinds of cyclical phenomena were found. (1) Oscillatory cycles consist of rhythmical raising and lowering of the floor of the mouth, with open nares. They have a definite respiratory function in introducing fresh air into the buccal cavity. (2) Ventilatory cycles involve opening and closing of the glottis and nares and renewal of a portion of the pulmonary gas. More muscles are involved and the pattern of muscular activity is more complex than in the oscillatory cycles. (3) Inflation cycles consist of a series of ventilation cycles, interrupted by an apneic pause. The intensity of the ventilatory cycles increases before this pause and decreases immediately thereafter. This results in a stepwise increase in pulmonary pressure, to a plateau (coincident with the pause) followed by a sudden or stepwise decrease.

The respiratory mechanism depends on the activity of a buccal force pump, which determines pulmonary pressure whose level is always slightly less than the peak pressure values of the ventilation cycles. The elevated pulmonary pressure is responsible for the expulsion of pulmonary gas during the second phase of the next ventilation cycle. This pressure is maintained by the elastic fibers (and the smooth masculature) of the lungs.
Morphogenesis of body segments and appendages during the larval stages of a common spiroboloid milliped
Authors: Berns Michael W.
Published: February 2005

Three‐dimensional, histological, and x‐ray techniques provide a picture of body segment and limb morphogenesis. Cell multiplication begins in the proliferation region (“meristem”) during the molt from the preceding instar. By four days post‐molt, the cells that will form the new segments are well under way in their anterior, lateral, and dorsal migration. It is suggested that after the anlagen for all the new segments are estabilshed, a mitotic wave commences in the most anterior anlagen and moves posteriorly during the remainder of the instar. When cell proliferation is complete, final differentiation of the segments takes place.

The process of limb formation is one of cell proliferation and perhaps migration. Each limb develops in a membranous pocket during the instar following the one in which its respective body segment was formed.
Ultrastructure of human labial salivary glands. I. Acinar secretory cells
Authors: Tandler Bernard , Denning Carolyn R. , Mandel Irwin D. , Kutscher Austin H.
Published: February 2005

The structure of human labial salivary gland acini was studied by light and electron microscopy. Contrary to previous reports, these glands were pure mucous in nature; no serous elements were present. The acinar cells were found in all stages of maturation. Immature cells were characterized by an extensive and highly organized rough‐surfaced endoplasmic reticulum. The Golgi complex was extremely prominent, consisting of stacks of flattened cisternae and swarms of small vesicles. Mucous droplets were almost completely absent. As secretory activity progressed, the endoplasmic reticulum involuted, while the Golgi cisternae became distended and formed many vacuoles. In mature mucous cells, the apical cytoplasm was filled with membrane‐bounded mucous droplets, and the nucleus was displaced basally. The droplets frequently showed great variation in density from cell to cell, and even within the same cell they sometimes were quite heterogeneous. They were liberated from the acinar cells by an apocrine process, so that droplets with intact limiting membranes were often observed in the acinar lumen. These droplets soon lysed, their contents fusing into streams of mucus. Occasionally during apocrine secretion a mucous cell failed to reconstitute its apical surface, and its entire contents spilled into the acinar lumen.

Unusual cytoplasmic inclusions were present in many of the acinar cells. These inclusions, which were surrounded by a single membrane, consisted of lipid droplets closely associated with bundles of fine filaments.
Ultrastructure of bovine parotid glands
Authors: Shackleford John M. , Wilborn Walter H.
Published: February 2005

Bovine parotid glands exhibit outstanding structural differences when compared with those of non‐ruminant mammals. The acini are tortuous, branched and lined with cells of different heights, imparting a scalloped appearance to acinar lumina. Numerous microvilli, ca. 1.5 μ in length, extend into the lumina and intercellular canaliculi. Intercellular canaliculi measure ca. 3 μ in diameter and interweave in close association with intercellular tissue spaces. Intercellular tissue spaces are separated from the extraacinar spaces across a basal lamina only, whereas junctional complexes guard canaliculi from direct continuity with tissue spaces and/or extraacinar spaces. Flattened cytoplasmic lamellae extend from adjacent acinar cells and loosely interdigitate with one another across the tissue spaces. Acinar cells contain more mitochondria and less granular endoplasmic reticulum than parotid glands of non‐ruminant mammals. Two types of secretory material, in the form of inclusions which vary in size and electron density, are present in the acinar cells. Intercalated ducts connect acini with striated ducts which in turn, empty into collecting ducts located between gland lobules. In terms of frequency of “basal infoldings” and numbers of mitochondria, striated ducts of calf parotid glands are not as well developed as those of certain other salivary glands. Myoepithelial cells are most often present at junctions of acini and intercalated ducts where they may attach to both acinar and ductal epithelium. Nerve “terminals” were not observed on the epithelial side of basement membranes in relation to the secretory cells.
Special cutaneous receptor organs of fish: III. The ampullary organs of Eigenmannia
Authors: Szamier R. Bruce , Wachtel Allen W.
Published: February 2005

Ampullary receptor organs of the South American weakly electric gymnotid fish Eigenmannia virescens consist of a pore at the surface of the skin, a canal through the epidermis, and the expanded basal end of the canal in the corium. The cavity of the organ contains a jelly that is filled with fine fibers. The canal wall consists of three to six layers of flattened cells that appear to be derived from the adjacent skin. Along the lumen of the organ the cells are joined by tight junctions. Usually there are four spherical receptor cells in the base of the organ. They are innervated by single neural terminals. These organs are compared to tuberous receptor organs found in the same species, and the functional significance of the fine structure observed in these cells is discussed.
Special cutaneous receptor organs of fish: IV. Ampullary organs of the nonelectric catfish, Kryptopterus
Authors: Wachtel Allen W. , Szamier R. Bruce
Published: February 2005

Ampullary organs of the transparent catfish, Kryptopterus bicirrhus, are present in large numbers on the head and in a regular pattern of lines on the body and fins. The organs lie in the epidermis, and have a pore that opens to the surface. Flattened cells form a roof and walls. On the floor of the organ there are a “sensory hillock,” composed of spherical receptor cells and columnar supporting cells, and a “secretory hillock” composed of columnar secretory cells. The receptor cells are nonciliated and have only afferent innervation. The organ cavity is filled with jelly. The organs are compared with ampullary organs of the weakly electric fish Eigenmannia, ampullae of Lorenzini of Raja, and small pit organs of Amiurus. Structural characteristics of the ampullary organs of Kryptopterus make them especially suitable for electrophysiological studies.
Electron microscopy of the normal and I131 treated thyroid gland of the newt, Notophthalmus viridescens
Authors: Hearing Vincent J. , Eppig Jr. John J.
Published: February 2005

The fine structure of the thyroid of the newt, Notophthalmus viridescens, was studied with the electron microscope. Specimens were injected I.P. with 30 μc of I131 and sample thryoids were examined at 12 hour intervals thereafter. The ultrastructure of the normal thyroid gland is described, and compared with that of the irradiated glands. The first visible ultrastructural change observed after injection of the radioiodin was a striking alteration of nuclear morphology. This effect was followed by an increase in the frequency of whorled lamellar structures, a decrease in the number of microvilli, and degeneration of the Golgi apparatus and endoplasmic reticulum. Further effects observed included an increase in the number of large cytoplasmic granules and a decrease in the number of smaller ones, the presence of autophagic vacuoles, and finally, an increase in the number of degenerated mitochondria.
Analysis of the embryonic sources and mechanisms of development of posterior levels of chick neural tubes
Authors: Criley Bruce B.
Published: February 2005

The mechanisms of development of posterior levels of neural tubes of chick embryos were analyzed by study of serial cross‐sections of a continuous series of normal embryos between 40 to 72 hours of incubation. Two extirpation experiments were performed in ovo on other embryos of the same stages. Descriptive studies revealed the presence of an overlap zone in which two types of neural tube formation occurred. Open neural tube formation (by fusion of neural folds) occurred dorsally in this region; closed neural tube formation (by canalization of solid medullary cord tissue) occurred ventrally. Extirpation of the posterior end of the neural plate produced defects within the lumbosacral region, indicating that the posterior neural plate participates in the formation of the lumbosacrum, and that the overlap zone is therefore in the lumbosacral region. Extirpation of the prospective neural tissue in the anterior end of the tail bud indicated that only the most posterior levels of the neural tube originate exclusively by cavitation of the tail bud. In both extirpation experiments a neural tube formed independently within the tail bud tissue, indicating that formation of the neural tube in this region is not dependent upon direct continuity with neural tissue anteriorly.
An autoradiographic analysis of yolk deposition in the cortex of the cecropia moth oocyte
Authors: Melius Melvin E. , Telfer William H.
Published: February 2005

The cecropia moth oocyte accumulates proteins from the blood during vitellogenesis; the proteins reach the oocyte by an intercellular route, are taken in by pinocytosis, and become components of the protein yolk spheres. Different proteins vary greatly in the extent to which they are incorporated into the yolk spheres. One objective of the work described in this paper was to determine where the selectivity of protein uptake occurs. An autoradiographic analysis of the uptake of tritiated blood proteins injected into the hemocoel indicated that there are at least two sites of selectivity – one between the hemocoel and the intercellular spaces of the follicular epithelium that surrounds each oocyte, and another between the intercellular spaces and the yolk spheres. Another objective was to determine if only proteins from the blood are deposited in the protein yolk spheres. Studies of the incorporation of tritiated leucine provided evidence that the ovary itself synthesizes proteins that are deposited in the yolk spheres along with the blood proteins. Finally, evidence is presented that the various regions of the oocyte cortex are not equally active in the deposition of yolk.
Oocyte‐follicle cell differentiation in two species of Amphineurans (Mollusca), Mopalia mucosa and Chaetopleura apiculata
Authors: Anderson Everett
Published: February 2005

Differentiating oocytes and associated follicle cells of two species of amphineurans (Mollusca) Mopalia muscosa and Chaetopleura apiculata have been studied by techniques of light and electron microscopy. In addition to the regularly occurring organelles, the ooplasm of young oocytes contains large, randomly situated, basophilic regions. These regions are not demonstrable in mature eggs.

As oocytes differentiate, lipid, pigment and protein‐carbohydrate yolk bodies accumulate within the ooplasm. Concomitant with the appearance of pigment and the protein carbohydrate containing yolk bodies, the saccules of the Golgi complex become filled with a dense material. Associated with the Golgi complex are cisternae of the rough endoplasmic reticulum which are filled with an electron opaque substance which is thought to be composed of protein synthesized by this organelle. That portion of the cisternae of the endoplasmic reticulum facing the Golgi complex shows evaginations. These evaginations are thought to finalize into protein containing vesicles that subsequently fuse with the Golgi complex. Thus, the Golgi complex in these oocytes might serve as a center for packaging and concentrating the protein used in the construction of the protein containing pigment or protein‐carbohydrate yolk bodies. The suggestion is made that the Golgi complex may also synthesize the carbohydrate portion of the formentioned yolk bodies.

In an adnuclear position in young oocytes are some acid mucopolysaccharide containing vacuolar bodies. In mature eggs, these structures are found within the peripheral ooplasm and we have referred to them as cortical granules. There is no alteration of these cortical granules during sperm activation.
Ultrastructure of thymic myoid cells
Authors: Bockman Dale E. , Winborn William B.
Published: February 2005

Mature myoid cells in the parenchyma of reptilian thymus contain all the organelles typical of striated muscle. The presence of both immature and degenerating stages indicates a turnover of myoid cells in the adult thymus. In the earlier stages of differentiation myoid cells resemble thymic epithelial cells. A close parallel exists between developing myoid cells, skeletal muscle differentiating in vitro, rhabdomyoma and rhabdomyosarcoma. Elaborate lattice‐like structures are formed by transverse tubules. These structures are compared with similar configurations which have been described in muscle and mitochondrial cristae.
Oogenesis in the annelid Enchytraeus albidus with special reference to the origin and cytochemistry of yolk
Authors: Dumont James N.
Published: February 2005

In the annelid Enchytraeus albidus the ovary is composed of packets containing eight synchronously developing oocytes. Each oocyte in the packet is connected, via a bridge, to a common cytoplasmic mass. Developmental synchrony of oocytes within individual packets is probably related to the ooplasmic continuity.

The young previtellogenic oocyte contains many polysomes, a few cisternae of smooth and rough endoplasmic reticulum, small Golgi complexes, and mitochondria. Many of the mitochondria are dumbbell‐shaped and may thus represent division stages.

Vitellogenesis is marked by the appearance of peripherally located lipid yolk and small, densely staining granules scattered throughout the ooplasm. There is an increase of smooth endoplasmic reticulum, mitochondria, and enlarged Golgi elements. Small multivesicular‐like bodies, the early stages of developing yolk, are derived from the Golgi complex. The mature yolk sphere is bipartite and consists of (a) a variable number of dense spheres, the core bodies, which are produced in the ooplasm by the Golgi complex and which become embedded in (b) a dense matrix. The electron opaque tracer, horseradish peroxidase is incorporated into the oocyte and deposited in the matrix suggesting that this component of the yolk sphere is obtained by micropinocytosis. Enzyme digestions and various cytochemical techniques suggest that the core bodies are rich in carbohydrate, probably as glyco‐ or mucoproteins, and that the matrix is rich in lipid.
The influence of the nerve on lower jaw regeneration in the adult newt, Triturus viridescens,
Authors: Finch Robert A.
Published: February 2005

The present investigation was undertaken in an attempt to determine the role played by the nerve in the regeneration of the lower jaw of the adult newt, Triturus viridescens. The results indicated that the number of nerve fibers normally available at the amputation surface was very low compared with that of the newt forelimb. Furthermore, denervation of the lower jaw reduced the number of nerve fibers available to an extremely low level and maintained the number at a low level for up to four weeks without intervening redenervations. The regenerative events in the denervated and amputated lower jaws were indistinguishable histologically from those in amputated jaws having normal innervation. This presented an apparent exception to the general rule that regeneration of external body parts is dependent on the nerve. Several possible explanations are proposed by which this apparent exception might be explained. The process following amputation might be an exaggerated form of wound healing and tissue regeneration which can occur in the absence of nerves. The tissues of the lower jaw might be more sensitive to the influence of those nerve fibers present. The nerve fibers themselves might be qualitatively different and thus exert a greater influence on the tissues.
Gustatory sense organs in the food canal of aphids
Authors: Wensler Rita J. , Filshie Barry K.
Published: February 2005

A sensory structure in the anterior region of the food canal of two species of aphid has been examined by light and electron microscopy. The dorsal wall is innervated by a total of 60 neurones which terminate, in groups, at 14 porous papillae on the cuticle. Paired papillae have also been detected in the ventral wall of this region. The fine structure of individual neurones and their grouping around papillae indicates a chemosensory function.

The examination of moulting aphids shows that the distal portions of dendrites are shed with the exuviae.
Structure of the integument of a fresh‐water teleost, Bagarius bagarius (Ham.) (Sisoridae, pisces)
Authors: Mittal A. K. , Munshi J. S. Datta
Published: February 2005

The skin of Bagarius bagarius (Ham.) is devoid of scales but is rough due to the presence of numerous pentagonal epidermal elevations, which are separated by deep furrows at regular intervals. These elevated pentagonal regions of the epidermis are covered by dead cornified cells in the form of caps. As the old cap goes off a new one is formed by the death of the underlying epidermal cells. The middle layer of the epidermis is mainly composed of well defined polygonal cells. Their cytoplasm is granular in nature and give reactions for protein bound sulphydryl groups. The stratum germinativum is composed of two types of basal cells, the columnar cells and the spherical cells.

The flask shaped mucous glands are restricted to the epidermal furrows and secrete either neutral or acidic mucopolysaccharides. Certain large specialysed granular cells are found in the epidermis which are grouped around the taste buds. These specialysed cells may be the photocytes.

Two layers of the dermis can be distinguished—the relatively thin stratum laxum and the thick stratum compactum. Dermal papillae mainly support the taste buds. The pigment cells are arranged in two layers in the dermis.

The subcutis is composed of loose connective tissues, richly infiltrated with the fat cells, nerves and blood capillaries.
Post emergence maturation of the eye of the adult black carpet beetle, Attagenus megatoma (Fab.): An electron microscope study
Authors: Butler Linda , Roppel Richard , Zeigler Joseph
Published: February 2005

The black carpet beetle, Attagenus megatoma (Fab.), has been reported to exhibit negative phototaxis immediately after emergence. In later adult life, after the period during which most oviposition has occurred, the beetles are found to be photopositive. The compound eyes of one‐day‐old (Post‐emergence) and nine‐day‐old (Post‐ovipositional) female beetles were studied by electron microscopy and a number of strong differences were found between eyes at the two ages. The corneal facets of one‐day eyes had the form of convex‐concave lenses, while those of nine‐day beetles were double‐convex lenses. The primary and secondary pigment cells of young eyes were large and contained much endoplasmic reticulum and little accessory pigment. In the older eyes the pigment cells were reduced and contained much pigment, the proportion of endoplasmic reticulum being greatly reduced by comparison with the one‐day eye. The cross‐sectional area of the rhabdom was greater in the older eye.

The possible relationships between age‐related changes in eye morphology and behavioral changes during the same period are discussed.
Egg transport in lizards
Authors: Cuellar Orlando
Published: February 2005

The reproductive tracts of several species of lizards were examined to understand the events assoclated with the transport of discharged oocytes following ovulation. At the onset of the reproductive cycle the regressed ovaries and oviducts appear as inconspicuous structures pressed against the dorsal body wall. As the reproductive cycle progresses, they undergo marked changes in position and size. The oviducts migrate ventrally and surround the growing ovarian oocytes, which move anteriorly where coelomic space is more abundant and eventually press intimately against the infundibulum. When ovulation occurs the ostium is in a remarkably strategic location for directly receiving the ovulated oocytes. The virtual isolation of the ovaries from the general coelom by the encapsulating oviducts, and the intimate association of the pre‐ovulatory oocytes with the infundibular ostium do not support the current concept advocating the migration of loose ova following ovulation. An alternative explanation for the “trans‐coelomic migratiion of ova” is proposed.
Functional morphology of the digestive tract epithelium in Phoronis vancouverensis (Pixell): An ultrastructural and histochemical study
Authors: Vandermeulen John H.
Published: February 2005

The ultrastructure of the gut regions of the marine filter‐feeder Phoronis vancouverensis was correlated with enzyme activity as revealed histochemically. The oesophagus, proventriculus, and stomach epithlia showed intense esterase and acid and alkaline phosphatase activity. The staining reaction was confined primarily to small globules in the apical cytoplasm of the epithlial cells. Electron micrographs of the same regions showed a high incidence of zymogenlike granules, with a corresponding abundance of ribosomes and of rough endoplasmic reticulum. Also, the proventricular and to a lesser extent the stomach epithelia were found to contain a large number of lipid bodies. This was confirmed with positive Sudan IV staining for fats.

The intestinal region of the gut was found devoid of esterase and phosphatase activity. The epithelial surface in this region was found elaborated into microvilli. The entire gut is ci iated. A new paired‐cilium apparatus is described in this phylum.

From these findings Phoronis vancouverensis is concluded to be suitably adapted to its continuous filter‐feeding existence, with the anterior gut epithelia synthesizing hydrolytic enzymes for release into the lumina of the proventriculus and stomach. Subsequently, in the hindgut the products of initial extra‐cellular digestion are absorbed via the microvilli and treated intracellularly within the intestinal epithelium. The proventriculus is further thought to function in lipid absorption and storage. The presence of chromaffin‐like granules observed in some proventricular and intestinal epithelial cells suggests that digestion in this phylum may in part be under neurosecretory control.
Microscopic anatomy of the cardiac ganglion of Limulus polyphemus
Authors: Bursey Charles R. , Pax Ralph A.
Published: February 2005

The morphology of the cardiac ganglion of Limulus polyphemus (L) was examined by reconstructions from stained serial sections. This ganglion is composed of two distinct parts: a fiber tract extending the entire length of the heart and a cellular portion underlying the fiber tract. The cellular portion extends continuously from the third pair of ostia to the posterior terminus of the heart. The mean number of ganglion cell bodies is 231. Most of the ganglion cells are located among the glial elements of the cellular portion. The greatest density of cells is found in segments 5 and 6. Six cell types are recognized: (1) large pigmented unipolar cells approximately 120 μ in diameter with distinct connective tissue capsules around them; (2) large pigmented bipolar cells approximately 120 μ in length which are also encapsulated; (3) pigmented multipolar cells approximately 80 μ in diameter which are free of capsules; (4) small pigmented bipolar cells approximately 40 μ in length which are encapsulated but which are found exclusively within the fiber tract; (5) non‐pigmented multipolar cells approximately 30 μ in diameter which are found scattered among the connective tissue elements of the cellular portion; and (6) small non‐pigmented cells approximately 10 μ in diameter which are found within the unipolar cell capsule and scattered among the connective tissue elements of the ganglion.

The variability in cell numbers and the random location of cells points toward non‐specific anatomical connectivity between elements of this ganglion.
Histogenesis of Swiss white mouse secondary palate from nine and one‐half days to fifteen and one‐half days In utero. I. Epithelial‐mesenchymal relationships—light and electron microscopy
Authors: Sweney L. R. , Shapiro B. L.
Published: February 2005

Development of the secondary palate in Swiss white mouse embroyos was studied from age nine‐and‐one‐half days in utero to the stage of mesenchymal coalescence in the secondary palate (approximately fifteen‐and‐one‐half days). The greatest changes observed occur in the mesenchyme. At early stages, mesenchymal cells underlying oral ectoderm of the head are few and only occasionally contact the ectoderm. Electron micrographs show large intercellular spaces between the ectodermal cells. As embryogenesis continues, the mesenchymal cells become more numerous, closer to each other and closer to the epithelium. Just prior to horizontal transposition of shelves, the mesenchymal cells spread farther from each other and from the palatal epithelium and epithelium of the palatal tip becomes stretched. Ultrastructurally the intercellular spaces between epithelial cells of the palate tip have become much smaller. Some mitochondria in some epithelial cells are swollen and have clear matrices and distorted cristae. The shelves become horizontal and meet in the midpalate. Cells with degeneration bodies are seen in the epithelial seam. The seam undergoes autolysis and is replaced by mesenchyme. The morphological changes described, particularly in the mesenchyme, may play an important role in determining the effect of various teratogens at different stages of palatal development. The changes in both mesenchyme and epithelial cells in the later stages may constitute part of the process of preparing shelves for fusion as postulated by Pourtois ('66).
The body wall of cheilostome bryozoa. III. The frontal wall of Watersipora arcuata banta, with a revision of the cryptocystidea
Authors: Banta William C.
Published: February 2005

(1) The frontal wall of the encrusting cheilostome, Watersipora arcuata is a one‐layered, evenly perforated calcareous shield which subdivides the metacoel into two compartments, the perigastric coelom and the hypostega. These compartments communicate through four and six “intrazoidal septulae” at the corners of the frontal wall. (2) The frontal wall develops by apposition independently of the ectocystal epitheca. The ascus develops as an invagination of the epitheca. These observations are consistent only with the view that the frontal wall of this species is a cryptocyst. (3) The terms “tremocyst,” “olocyst,” and “pleurocyst” are poorly understood and ambiguously defined; they should not be used until more information is available. (4) The taxa Anasca, Ascophora, Ascophora Imperfecta, and Ascophora Vera are polyphyletic and should ge dropped and replaced by Silén's (1942) more natural taxa. Silén's Cryptocystidea should be enlarged to include Watersipora and related ascusbearing cheilostomes.
Observations on the pineal system in the hamster. I. Relations of the superficial and deep pineal to the epithalamus
Authors: Sheridan Michael N. , Reiter Russel J.
Published: February 2005

A mass of pineal tissue has been observed associated with the habenular commissure and the apex of the pineal recess in the golden hamster. Previously, it had been thought that all of the pineal system in the hamster was located at the confluence of sinuses just beneath the skull. To distinguish the two components of the pineal system, that in the dural position is called the superficial pineal and the mass associated with the habenular commissure is called the deep pineal.
Observations on the pineal system in the hamster. II. Fine structure of the deep pineal
Authors: Sheridan Michael N. , Reiter Russel J.
Published: February 2005

The fine structure of the deep pineal, a mass of pineal parenchyma positioned in the roof of and caudal to the pineal recess is described. The fine structure of deep pineal is similar to earlier descriptions of superficial pineal.

The parenchymal cell displays abundant mitochondria, many of which contain a tubular internal structure, a prominent Golgi apparatus, and smooth and granular endoplasmic reticulum.

The parenchymal cells are extensively branched and terminate in club‐like endings. Pineal cell process terminations contain a profusion of vesicles of varying size, many of which contain an electron‐dense granule. The granules are presumed to be associated with the secretory product of the parenchymal cell.

The deep, unlike the superficial, pineal contains a relatively high concentration of glial cells and processes, some of which contain mitochondria with a unique internal structure.
Salivary glands of heteromyid rodents, with a summary of the literature on rodent submandibular gland morphology
Authors: Flon Helen , Gerstner Robert , Mitchell Ormond G. , Feldman Audrey
Published: February 2005

The principal parenchymal elements of the submandibular glands of the heteromyid rodents Dipodomys merriami, Perognathus longimembris, Perognathus fallax, Perognathus penicillatus and Perognathus baileyi consist of acini, granular tubules and striated ducts.

Acinar cells of the four species of Perognathus are aniline blue, PAS (magenta) and Alcian blue (pH 2.5) positive and metachromatic with toluidine blue and safranin. The granules of the tubule cells are orthochromatic and react with aniline blue, orange G, the PAS reagent (deep pink) and the tryptophan indicator, xanthydrol. Acinar and tubule cells of D. merriami exhibit similar reactions except for the Alcian blue stain. Acinar cells of D. merriami do not react with Alcian blue.

Submandibular glands of D. merriami exhibit a sexual dimorphism of the granular tubules. There is little observable difference between the sexes in the species of Perognathus but the ratio of granular tubules to acinar elements, the degree of hypertrophy of the tubules, and the amount of mucosubstance and protein (granules) contained in their cells are different in the four species studied.

Since these desert rodents have similar habitats and habits, the differences observed between the two heteromyid subfamilies studied, as well as among the four members of a single subfamily, suggest that these are inherent species variations rather than variations of adaptation to environment.
Morphology of ovarian changes in the garden lizard, Calotes versicolor
Authors: Varma Santosh Kumari
Published: February 2005

Ovarian changes during the reproductive cycle of the oviparous garden lizard (Calotes versicolor) are described. It ovulates from last week of June to first week of September but most often in July and August when the monsoon occurs. The number of eggs ovulated vary from 10 to 32. After ovulation, the ovaries are reduced in size. From October to May, the ovaries contain small pre‐vitellogenic follicles, which increase in size in June when most of yolk deposition occurs. Several nuclei are seen in the ooplasm of pre‐vitellogenic follicles; they are finally absorbed before yolk deposition starts. Follicular atresia generally occurs in follicles with polymorphic granulosae, in post‐ovulatory ovaries. Presumably interstitial gland cells are formed by the hypertrophy of the theca interna cells of atretic follicles. Pre‐ovulatory follicles have highly vascularized thecae and invaginations of the follicular epithelium. After ovulation, the follicle cells hypertrophy to form the luteal cell mass filling the follicular cavity. Fibroblasts, which appear to arise from the theca interna, invade the luteal cell mass and form septa. Capillaries occur in the luteal cell mass.
The ultrastructure of the pygidial defence glands of the carabid Pterostichus madidus F
Authors: Forsyth D. J.
Published: February 2005

Pygidial defence glands, which are universal in Caraboidea, are paired, cuticular invaginations of the body wall.

In Pterostichus madidus F. the glands contain a nauseous, corrosive secretion that can be discharged forcibly to deter attack by predators. The cells producing the secretion are of one type only. Electronmicroscopy shows that the ducts which drain these cells are not intracellular but are separated from the cell contents by a plasma membrane. The cuticular walls of the duct appear to effectively screen the cell from the disruptive effect of its final products of secretion. The duct‐carrying epidermal cells which are modifications of the epidermis covering the rest of the gland support the ducts from the secretory vesicles to their entry into the central lumen of each secretory lobe. There is a single duct‐carrying cell around each duct.
The biology of cartilage. II. Invertebrate cartilages: Squid head cartilage
Authors: Philpott Delbert E. , Person Philip
Published: February 2005

In both light and electron microscopes, head cartilage from the squid Loligo pealii strongly resembles vertebrate hyaline cartilage. The tissue is characterized by the presence of irregularly‐shaped cells suspended in an abundant matrix. Cell and matrix contents stain metachromatically with cationic dyes such as toluidin blue. Each cell gives off extensions which ramify via a network of channels throughout the matrix. Thereby, a system of inter‐connecting canaliculi is established, with many similarities to the intercanalicular systems seen in vertebrate bone and cartilage tissues. In the electron microscope, the squid cartilage cells are seen to have very abundant endoplasmic reticulum and Golgi complex material. Mitochondrial transformations involving loss of cristae, the appearance of filaments in the mitochondrial matrix, and figures suggesting budding, also occur. Nuclear pores are numerous and easily detected. The matrix is characterized by the presence of a system of decussating fibrils which form polygonal figures, with granules usually evident at the points of intersection of fibrils. By chemical analysis the tissue contains 3‐ and 4‐hydroxyproline and hydroxylysine. Preliminary wide single x‐ray diffractions show a pattern characteristic for unoriented collagens, with 12 Å (intermolecular) and 2.86 Å (helix) reflections.
Fine structure of spermatogonia and intercellular bridges in Macaca nemestrina
Authors: Gondos Bernard , Zemjanis Raimunts
Published: February 2005

Spermatogonia of the monkey, Macaca nemestrina, were studied with the electron microscope. The spermatogonial nucleus is characterized by dense homogeneous chromatin and an eccentric nucleolus with a prominent surrounding clear zone. Cytoplasm consists chiefly of free ribosomes and vesicular endoplasmic reticulum. Scattered mitochondria with closely spaced transverse cristae are arranged singly and in pairs separated by thin electron‐dense bands. Binucleated spermatogonia resemble other spermatogonia in their ultrastructural characteristics, but contain an increased number of lysosome‐like structures and degenerating mitochondria.

Spermatogonial interconnections are of two types: broad cytoplasmic connections and narrow intercellular bridges. Connected cells are always identical in appearance and stage of maturation. Multiple connections occur. Interconnection of spermatogonia provides a syncytial type of arrangement which allows synchronization of differentiation and results in similar apperance of adjoining cells. Similarity of regressive changes in adjacent degenerating cells is explained by the presence of intercellular bridges.
Sense organs of a thysanuran, Ctenolepisma lineata pilifera, with special reference to those on the antennal flagellum (Thysanura, Lepismatidae)
Authors: Slifer Eleanor H. , Skkhon Sant S.
Published: February 2005

Six types of sense organs are present on the antennal flagellum of Ctenolepisma lineata pilifera: tactile hairs, trichobothria, thick‐walled chemoreceptors, small thin‐walled chemoreceptors and coeloconic chemoreceptors. The number, size and distribution on the antenna of each type have been recorded. The base of the tactile hair is more complex than is that of other insects examined earlier. Trichobothria, long, slender hairs that oscillate in a gentle puff of air, are an unusal feature in insects and especially so for the antenna. The two types of thin‐walled chemoreceptors differ in shape, size and in the structure of their walls and internal parts. A pocket‐like depression of the floor of the cavity in which the peg of the coeloconic sense organ is set has not been found in earlier studies. Its function is unknown.

The axons from the sensory neurons extend along the inner surface of the antennal epidermis as a sheet of fibers lining the antennal lumen. Near the pedicel the axons leave the epidermis and join to form the antennal nerve.

A few observations on sense organs on appendages other than the antennae and some notes on behavior are included.