NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
Medical Officers of the Army of India.
33
Practical Conclusions.
Grassi, Celli and others basing their suggestions on the experiment of Drs.
* Campagna Romana.
Low and Sambon, who spent two months
in the most feverish part of Italy * and
who by shutting themselves up in a mosquito-proof hut at sundown, thereby
escaping malarial fever, propose perforated zinc houses (mosquito-proof) to dwell
in. Few persons in India, after a noonday temperature of 117º F. in the shade
would care to shut themselves up in such a cage. To put the native population,
men, women and children, who sometimes have only sufficient money to keep
body and soul together, under mosquito nets or in mosquito-proof houses is out
of the question.
To cleanse the " Augean stable " of anopheles is a task only possible to
Hercules himself.
Get rid of puddles by all means, but I doubt whether, even if the whole
population of India were put to the work of filling up all the puddles during the
rains, the results would justify the expense.
The paddyfields, which are the main source of food throughout a great
part of India, will have to be abolished. Is the population to starve in the mean-
time ? Get rid of all the pools and puddles in India, and you will only find that
the anopheles will change its habitat ; or abolish anopheles altogether, and how do
we know that we shall be rid of malaria ? My view is that the malarial parasite is
trimorphic and that there is a phase (extra-corporeal) yet to be discovered.
The means of preventing the spread of malaria lie in two directions : (1) in
the free use of quinine ; (2) in the segregation of all suffering from ague.
Quinine, in a few cases I have noted, prevents the impregnation of the macro-
gamete by the flagellum of the microgamete and the zygotes fail to develop in
the stomach of the anopheles. Quinine is therefore useful in checking the endo-
genous as well as the exogenous evolution of the Laveran's bodies. The segre-
gation of infected individuals will be as difficult a task as the destruction of the
anopheles.
The 27th January 1901.
Zoological Gleanings from the Royal Indian Marine Survey
Ship Investigator.
BY
A. W. ALCOCK, M.B., C.M.Z.S., F.G.S.,
MAJOR, I.M.S.,
Superintendent of the Indian Museum and Professor of Zoology in the Medical College of Calcutta,
formerly Surgeon-Naturalist to the Indian Marine Survey.
" I l l e g i b l e w o r d π ó δ ε ξ ι ς I l l e g i b l e w o r d δ ε , I l l e g i b l e w o r d ς μ ή I l l e g i b l e w o r d ε I l l e g i b l e w o r d I l l e g i b l e w o r d γ ε ν ό μ ε ν α I l l e g i b l e w o r d I l l e g i b l e w o r d I l l e g i b l e w o r d ρ ό ν I l l e g i b l e w o r d
I l l e g i b l e w o r d ξ ί I l l e g i b l e w o r d η λ α γ έ ν η I l l e g i b l e w o r d α ι . " H e r o d . H i s t . A .
Introductory.
So many of the biological observations made through the medium of the
" Investigator " are buried in reports that are not accessible, and so many are
scattered through " systematic " papers where they are easily overlooked, that
I have thought it advisable to collect and classify, as a supplement to the
Summary of the Deep-sea Zoological Work published in these Memoirs in 1899,
all such observations as have been recorded since I first became connected with
the ship, together with many hitherto unpublished facts selected from my
Journal.
I have endeavoured to make this present summary useful to my successors
in the Marine Survey by embodying in it certain references to the literature of
some of the subjects treated. These lists of references are not complete enough
to be dignified by the name of bibliography, but they will answer their purpose
if they serve as beacons to the surgeon-naturalist who finds himself embarked
on these seas for the first time, marking out some of the channels of inquiry that
are open to him.
The contents of this somewhat miscellaneous paper are grouped under the
following headings:
—
I. Illustrations of Commensalism from the R. I. M. S. Investigator " :—
1. Among Sponges;
2.Amo n g Z o o p h y t e s ;
3.Among Echinoderms;
4. Among Crustacea;
36
Scientific Memoirs by
5. Among Mollusca ;
6, Among Fishes.
II. Some Notes on Sexual Characters, Pairing, and Viviparity, among
Marine Animals :—
I. Pairing and Parental Care among Echinoderms ;
2. On Secondary Sexual Characters and Pairing among Crustacea ;
3. On Certain Primary Sexual Characters in Certain Bony Fishes ;
4. On Certain Secondary Sexual Characters in Certain Bony Fishes ;
5. On Pairing among Eels ;
6. On Viviparous Bony Fishes ;
7. On Viviparous Elasmobranch Fishes.
III. On the Sounds made by Certain Marine Animals :—
1 .
S o u n d s m a d e b y C r u s t a c e a ;
2. Sounds made by Fishes.
IV. Miscellaneous Notes on Stalk-eyed Crustacea;—
1. The Early Larval Stages of Hippa asiatica, Thenus orientalis, and Nephrops
andamanica.
2. On Some Curious Habits of Land Hermit-crabs ;
3. On the Courting attitudes of the Fiddler-crab, Gelasimus annulipes.
4. On the Habits of some Indian species of Ocypode crabs.
5. Some Protective Disguises among Higher Crustacea.
6. On the Geographical Distribution of Varuna literata, Plagusia squamosa,
and Carcinus mœnas.
V. Some Instances of Protective and Warning Colouration.
VI. On the Phosphorescence of Certain Marine Invertebrates.
VII. Notes on some Peculiarities of Food.
VIII. Stray Notes on Sauropsida.
I may add that the observations brought together in these pages were made,
for the most part, off the east coast of the Peninsula, between False Point and
Masulipatam, where for several surveying-seasons the " Investigator" remained
at work for periods of three or four months together ; and also in the Laccadives
and off the neighbouring parts of the Malabar coast, and among some of the
eastern and northern islets of the Andamans, where, during my time, the ship
made occasional short visits in order to fix positions, or to look for suspected
shoals, or to land or pick up boat-parties.
Though every possible assistance was always given to the Naturalist
zoological interests could, necessarily, never decide the main movements of the
ship, so that we were never able to visit South Sentinel Island—where alone,
within Indian limits, Birgus latro is found—during the breeding season of that
interesting land-crab—to look for its larvæ. The honour, therefore of discover-
ing that the larva of Birgus is a zoæa and lives in the sea, belongs to that
Medical Officers of the Army of India.
accomplished and successful naturalist Dr. A Willey, who has recently been work-
ing in the seas of the East Indian Archipelago. Dr. Willey (see Borradaile,
P. Z. S. 1899, page 938) saw, in the month of January, at one of the islands
of the Loyalty Group, hatching zo æas being washed off a female Birgus
into the sea. The month of January is said, by residents at Port Blair, to be
the breeding season of Birgus at South Sentinel.
I.—Illustrations of Commensalism from the R. I. M. S.
" Investigator."
The term " commensalism " has been used with a certain amount of laxity
to cover everything, from the almost chance occurrence of an Amphipod crusta-
cean in the crevice of a sponge, to the fixed and constant association for mutual
benefit that subsists between, say, the hermit-crab Parapagurus pilosimanus
and the sea-anemone Epizoanthus.
This looseness of language is due to a certain elasticity of the subject. When
two non-parasitic animals are found in company, though we may not be able to
discover any bond between them, yet we are inclined to include the occurrence in
our records on account of its potential importance, for out of such seeming
chance unions all admitted instances of commensalism must have had their
origin.
Though we are not in a position to insist on any rigid definition of the term,
I shall, in the following selections from my experience in these seas, lay stress
only upon cases in which both of the commensals in any given partnership appear
to be adapted to one another, or in which one of them appears to have undergone
some adaptation to the other without injuriously affecting that other.
References to the general subject of Commensalism: VAN BENEDEN, Sur le Commen
salisme dans le Règne Animal, B r u s s e l l s , 1 8 6 9 ( B u l l . A c a d . R o y . B e l g i q u e , V o l . X X V I I I ) ,
and Animal Parasites and Messmates (International Scientific Series )
In BOUVIER, Bull. Soc. Philomath. Paris (8) V. 1892-93, pp. 143-149, a bibliography
containing some valuable references will be found.
I have not seen the paper by O. HERTWIG, entitled Die Symbiose im Thierreich.
1. Commensalism among Sponges.
Many kinds of non-parasitic marine animals find a convenient shelter within
the cavities and tissues of sponges and Zoophytes, but we are here concerned
only with cases in which it can be shown, or reasonably believed, that the associ-
ation has gone beyond the casual stage.
Scientific Memoirs by
Among the Sponges collected by the " Investigator" we commonly find that
the anchoring-ropes of the Hyalonematidœ are—as has been abundantly noticed
and commented upon elsewhere—encrusted with zoophytes of the genus Palythoa
and with Cirripede crustaceans of several species. The connexion here, however,
is probably accidental, because we do sometimes find both dead and living shells
and dead corals invested with both Palythoa and Scalpellum.
But when, in the depths of the Andaman Sea, we meet with the feeble little
macrurous crustacean Richardina spongicola entangled in the Hexactinellid
sponge Hyalonema masoni, and not elsewhere, we are inclined to suspect that the
relation between the two animals is in some way a necessary one. The nearest
relatives of Richardina also live imprisoned in Hexactinellid sponges : these are
Spongicola venusta, which is habitually found in Euplectella, and Spongicola
Koehleri, which is found in Regadrella phœnix. The species of Stenopusculus
also—a genus allied to Spongicola—commonly live with sea-anemones.
Another very good instance of commensalism, in which a sponge plays a
part, has often been observed on reefs of the Andamans, where the little
weak inoffensive crab Cryptodromia pileifera is never found unprotected by a
sponge—each crab being completely concealed beneath a little tightly-fitting
sponge shaped like a cap. But, of course, sheltering under sponges and Ascidians
is a well-known family-habit with the Dromiidœ.
References to the commensals of Hexactinellid sponges will be found in the following
papers :—
J. E. Gray, in Ann. Mag. Nat. Hist. (3) XVIII. 1866, p. 489, and XIX, 1867
p .
4 4 .
Semper, in Wiegmann's Archiv für Naturges. XXXIII, 1867, i. p. 84 ; and
Ann. Mag. Nat. Hist. (4) II. 1868, p. 26.
T. J. Moore, in Ann. Mag. Nat. Hist. (4) III. 1869, p. 198.
Willemoes Suhm, in Zeitschrift für wiss. Zool. XXVI, 1876, Appendix, p. lxxiv.
Miers, in Journ. Linn. Soc. Zool., XIII. 1878, p. 507.
Also in the " Challenger" Reports, by F. E. Schulze, on the Hexactinellid Sponges ;
and in Filhol, La Vie au Fond des Mers, Paris, 1885.
On the general subject of commensals of Sponges see :—
H. J. Carter, Parasites of the Spongida, in Ann. Mag. Nat. Hist. (5) II. 1878,
p. 157.
Weltner's summaries in Wiegmann's Archiv für Naturges. for 1887, 1888, 1890,
1892, 1894.
The following are some of the papers on Sponges and Crustacea as commensals:—
Hesse, Ann. Sci. Nat. Zool. (4) XV 1861, page 105: Henderson, Challenger Narra-
tive,Vol.,1, pt. 2, p. 899: Scott, Proc. Nat. Hist. Soc. Glasgow, 1886, p. 146: Senoner
Zool. Garten, XXVII, 1886, p. 92 : Bidder on Celesia, Zoologischer J ahresbericht, 1893,
Porifera p. 10 (Colesia, Atti. Soc. Ligustic. Sci. Nat. Genova, IV, 1893, p. 217) .
Medical Officers of the Army of India.
2. Commensalism among Zoophytes.
There are no marine animals that are more ready to attach themselves
to others than are the Actiniarian Zoophytes. Many of these attachments . may, be
conveniently classed as casual, others without doubt. exhibit the bond of mutual
necessity and include some of the most perfect instances of commensalism known,
while between these two extremes there are numerous gradations.
One of the most finished cases of commensalism that has come under my own
observation,. in these seas, is that existing between an undescribed species of
colony-forming sea-anemones belonging, or closely related, to the genus M a m i l -
lifera, and the hermit-crab Chlaenopagurns andersoni.
This hermit-crab grows to a considerable size (a large male being 63 mm.
in length from the rostrum to the point where the flexure of the abdomen begins),
and lives at a considerable depth (102 fathoms off the Malabar coast) where
we know that mollusk-shells large enough to accommodate an animal of this size:
are uncommon. The protection, then, that this hermit-crab requires is furnished,
not by a shell at all, but by a sheet or blanket formed by the soft
flexible-coerosarc of a colony of polyps. The hermit-crab holds the sheet over its back,
by tucking one end of it under its telson and hook-like swimmerets, and by grasp-
ing the corners of the other end in the pincers of its penultimate pair of thoracic
legs. When the full protection of the sheet is not required, these legs are flexed
in repose, and the sheet lies loose on the hermit-crab's abdomen ; but when the
hermit-crab wishes to conceal itself, it extends and pronates these legs,. so
that the sheet is drawn right over its cephalo-thorax. Captain A. R. S.
A n d e r s o n
w h o o b s e r v e d t h e a n i m a l i n l i f e , s a y s t h a t.
this action is particularly neatly per-
formed.
The examination of a large series of specimens, in ali stages of growth,.
shows that the partnership begins, at an early period of the life of both animals,
by the settling of the parent-polyp of the , colony on the telson of the little
hermit-crab. As the hermit-crab grows, the investing-polyp increases in size,
pail passe, by budding, so that in all stages of its existence the hermit-crab,
has a cloak of suitable dimensions. On the other hand, the. nutrition and
growth of the polyps is.assured by the fact that the agency of the 'crab changes
them from sedentary to locomotive-animals.
The well-known partnership that subsists between the colony-forming sea
anemone Epizoanthus and the deep-sea hermit-crab Parapagurus
has been often illustrated in the dredgings of the Investigator.' In this case,
as has been explained by Verrill, Bouvier, and others, the partnership begins,
L
-
40
Scientific Memoirs by
through the mediation of an empty mollusk-shell, the cavity of which is taken
possession of by the hermit-crab and the outer surface by the Epizoanthus.
As the two animals grow, the shell disappears by gradual absorption, until
at last the hermit-crab comes to be lodged in a burrow tunnelled out of the
yielding cœnosarc of the Epizoanthus-colony itself. In this way the recurring
difficulty of finding a graduated series of empty shells—which we have reason
to believe is a real difficulty in the ocean abysses, where strong-shelled
gastropod mollusks are not particularly abundant—is avoided by the growing
h e r mi t - c r a b ; wh i l e , o n t h e o t h e r h a n d , t h e r i s k o f l o s i n g , e v e n t e mp o r a r i l y , i t s
valuable locomotive agent is obviated by the action of the Epizoanthus.
In the two foregoing instances, the union between the two animals may be
regarded as a necessity of existence for both ; but in the following six cases
in which, in these seas, hermit-crabs and zoophytes have been found in company,
it is impossible to say how far the association is necessary, though it is easy to
understand that it is advantageous to both parties. These six cases are :
—
(a) Parapagurus andersoni from deep water (430-719 fathoms) living in
shells of Natica and Bathybembix invested by a sea-anemone.
(b) Parapagurus minutus from deep water (719 fathoms) living in shells
of Dentalium, one of which is encrusted by a colony of a species
of Palythoa.
(c) Parapagurus affinis from deep water (430 fathoms) living in shells of
Natica, some of which are invested by a sea-anemone.
(d) Sympagurus monstrosus from deepish water (145-250 fathoms) living
chiefly in shells of Rostellaria delicatula, most of which carry a
sea-anemone.
(e) Paguristes puniceus from deepish water (145-250 fathoms) living in
shells of Rostellaria delicatula many of which are encrusted with
a colony of a species of Zoanthoid.
(f)) Paguristes sp. nov . from 55 fathoms living in shells of Murex,
Rana, etc., many of which are invested by a sea-anemone besides
being encrusted by a small species of Balanoid Cirripede.
In all these cases it is hard to say whether the association is casual, or
necessary : the animals lie beyond the reach of observation, so that we cannot
tell whether the hermit-crab is merely a chance and temporary occupant of a
shell that is being also used by a zoophyte, or whether—as in the well-known case
of Adamsia palliata and Eupagurus prideauxii of European seas—the hermit-
crab, when compelled to seek a larger shell, detaches the sea-anemone from its
old shell and re-attaches it to its new one. Nor can we tell whether—as in the
Medical Officers of the Army of India.
41
case of Adamsia—the sea-anemone lives on quite happily alone if its hermit-crab
partner dies.
Another similarly doubtful case is that of the sea-anemone which, in these
seas, almost always lives with the Oxystome crab Dorippe jacchino. For protection
this crab commonly holds a dead lamellibranch shell over its back, and to the
upper surface of this shell a sea-anemone is usually attached. It looks, however,
as if there were some special purpose in this association, because I have never
observed a sea-anemone keeping company with the Dromioid crab Conchoecetes
artificiosus although this crab has the same habit of roofing itself over with a
dead lamellibranch shell. Very possibly also the sea-anemone which fixes itself
on the carapace of large adults of the Oxyrhynch crabs Doclea ovis and Doclea
canalifera is a true commensal species.
The alliances that exist between the little corals Heterocyathus and
Heteropsammia, on the one hand, and certain species of Sipunculoid worms on the
other hand, have been frequently noticed in zoological literature. The worm oc-
cupies a tunnel in the base of the living coral, from which it can, on occasion,
protrude the anterior part of its body—repaying the coral for this accommodation
by acting as a locomotive. Three species of Heterocyathus and three of
Heteropsammia are found in these seas, and when serving on board the " Investi-
gator," I once, for a short time, kept some specimens of Heteropsammia aphroāes
alive to watch how the commensal worms dragged their coral partners about.
This, as several authors have remarked, is an undoubted instance of com-
mensalism, for both parties are equally benefited by their union.
One of the happiest instances of commensalism observed on board the
" Investigator" is that exhibited by the gymnoblastic Hydroid Stylactis minoi
and the Scorpaenoid fish Minous inermis, which was first reported by me in the
Annals and Magazine of Natural History for September 1892, and has since
been abundantly verified.
Many of the fishes of the Scorpaenoid family either live on the sea-
bottom or haunt the crevices of reefs, and are, by reason of their mottled
colouration and by a profusion of wavy cutaneous filaments, difficult to detect
among shingle and rocks encrusted by seaweed and zoophytes.
Minous inermis has few cutaneous filaments, but is always more or less
invested with Hydroid polyps of one particular species. We have now taken the
fish at four widely distant localities and in considerable quantity, and every indi-
vidual has these polyps growing on its skin, especially in the neighbourhood of
the throat. There can be no doubt that the polyps are a useful disguise to the
fish, and that, on the other hand, their own attachment to a locomotive animal
42 Scientific Memoirs by
must be an equal advantage to themselves. That the polyps are not parasites is
proved by the facts (1) that the nutritive zooids of the colony have a proper
mouth and a prominent peristome fully equipped with tentacles for catching food,
and (2) that in any colony numerous zooids may be found with their gastric
cavity crammed with food, which they must have caught for themselves.
In the following six cases of symbiosis, in which Zoophytes are concerned,
the element of reciprocity seems to be wanting, so that it is doubtful whether they
should be cited as cases of true commensalism :—
(a) The feeble little Oxyrhynch (Pisine) crab Hoplophrys oatesi lives among
the branches of the Alcyonarian Zoophyte Spongodes prox. pustulosa. The polyp
colony has a brilliant white coenosarc and pink-tipped zooids, while the living
crab is porcelain-white with pink spines on its carapace and pink-banded legs,
the colours of the two animals matching so completely that the crab escapes
notice. The advantage to the crab is obvious, and there can be little doubt that
the animal has been specially adapted to its habitat ; but there seems to be no
corresponding benefit to the Spongodes.
(b) A parallel case is that of the little Xanthoid crab Liomera sodalis, the
red and yellow colour-markings of which are exactly those of the Alcyonarian
( Solenocaulon sp.) in whose hollow branches it dwells.
(c) The diminutive Thalassinoid lobster Iconaxiopsis laccadivensis,—a
pair (male and egg-laden female) of which were taken on the branches of the
Gorgonacean Zoophyte Calypterinus allmanni, is another instance of a feeble
crustacean escaping detection by closely resembling in colour the host with
which it lives.
(d) A Pennatulid Zoophyte of the genus Pteroeides, found in these seas,
gives similar cover to no less than three different kinds of lurking Crustaceans
— a
P o r c e l l a n a ,
a n
A l p h e u s ,
a n d a C r a n g o n o i d — a l l o f w h i c h a r e s p e c i a l l y m o d i f i e d
for their habitat. The coenosarc and zooids of the Pteroeides are of a trans-
parent grey colour, and each zooid is defined by a ring of dark grey pigment.
To match this exactly, the crustacean commensals are transparent grey marked
with spots and rings of dark grey.
(e) In stocks of the Oculinoid coral Lophohelia investigatoris, dredged off
the Travancore coast in 430 fathoms, numerous specimens of a Polychaete
worm were found, the connexion being undoubtedly a permanent one. The
worms were living, not like parasites inside the branches of the coral, but inside
tunnels formed by a crust of scleroderm that connected two neighbouring bran-
ches.
(f ) In the branches of Calypterinus allmani, dredged in the Laccadive
Sea at 705 fathoms, several specimens of a slender Polychaete worm were