New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1879-05-02
NEW PUBLICATIONS.
MosELEYs NOTES OF A NATURALIST.


scientific staff Of the Challenger" and accom-
panied the Expedition around the world under the
command of Captain Sir G. S. Mares and Captain
F. L. Thomson, in the years 1S72-76. lie mas
mined to present the results of his obser vatlons III
shape suitable for popular reading, and free from
the technicalities of scientific formulas. Inc Work
contains an ample fund oS information with regard
TO the fauna and fora of the distant lanus that
were visited by the writer, with details OF physi-
cal geography, and the manners and customs OF the
native populations, much of which Is of novel
character. and all of it stamped with the freshness
and viyacity of personal experience.
An interesting chapter is devoted to life on the
ocean surface and in the deep which is valuable
as lucid summary of the fruits Oh
scientific exploration in different regions
of the ocean. The surface water OF the
omen sea. we are informed is full of vegetable life
In high northern and southern ATTITUDES. diatoms
were found in so great abundance as to color the ice
with their debris, change the TINT of the
water. and cover the deep sea bottom with
n sihcicus deposit of their skeletons
Other 'lowly-organized alge abound in tropi-
cal seas They occur in the water as small
brown faggots Of minute threads, resembling tiny
fragments of chopped hay. So strongly Is the
light reflected from the minute bundles oil the
algfe that the waters Of the sea IN when they
abound when lighted up by sunlight, appear as
if filed with small particles OF shining mica. BE-
sides these smaller age living in the open ocean,
there are abundance of several species OF larger
seaweeds on the surface waters. The Gulf weed
of the Sargasso Sea in the Atlantic is well known
When dried or preserved it is of brown color, but
when living its bright yellow tints present an
agreeable contrast with the deep blue OF the open
Atlantic. wide area covered with seaweeds cor
responding to the SargassO Sea occurs In the North
Pacific Ocean. The existence of this vast marine
vegetation affords an abundant supply for the sup
port of animal life Plants are as necessary in the
open sea as on land TO form the starting point of the
organic circle by building up the compounds re-
CURED by animals as their food. The alga, though
brown in appearance, contain chlOrOphyl, the
same green coorlng matter which tinges the leaves
of the trees and plants on land, and forms " the
only starting-pont and foundatiOn-stone Of life"
The Sargasso Sea has its own peculiar fauna
especially adapted to life among the Gulf Weed
There is a small fish, allied to the Angler, with long
aIm-like fore fins with which it clings to the
punches of Weed. 1t makes nest of the Weed,
binding together a gobular mass, as large as
Dutch cheese, by means OF long gelatnous strings
which it forms for the purpose. The eggs of the
fish are placed in the centre of the nest All the In
habitants of tho Gulf Weed are remarkably colored
for purposes of protection and cOncealment, exactly
like the Weed itself The shrmps and crabs which
swarm in the Weed are exactly OF the same shade OF
yellow as the Weed, and have white markings upon
their bodies to represent species of bTyozoOn with
which it is incrusted. Almost all classes of land
animals, the author affirms seem to have con-
tributed to the marine fauna certain forms which
have become IN most cases extremely modified TO
suit their changed mode of existence. Amongst
mammals there are the whales and polposes,
the ancestors of which are believed long after they
had deserted the land and had taken to marine
existence TO have come on shore regularly, like the
seal at certain seasons to breed but at length ac-
oured the power of even rearing their young in the
open sea.
Without the vegetation and the fauna of the
ocean surface, life would be impossible, OF only
extremely scanty i'll the deep-sea bottom. Although
the depth of the is small III proportion to
the vasness of its expanse it is still so great as to
be difficult of adequate realization. The greatest
depth which has as yet been ascertained by sound
ing is in the Northwest Pacific Ocean, and amounts
to about five miles and a quarter. The average
depth of the ocean between the sixtieth degree of
north latitude and the same degree of south lati-
tude is about three miles, or $500 fathOms. The
great depth of five miles occurs only exceptionally
over very small areas. The conditions under which
life exists in the deep sea are very remarkable.
The pressure exerted by the water at great depths
is enormous, and almost beyond comprehension
1t amounts to about ton weight on the square inch
for every thousand fathOms of depth so that at the
depth of $500 fathOms, there is pressure of two
tons and half on every square inch of surface,
which may be cOntrasted with the 10 pounds
per square inch to which we are accustomed
at the level Of the surface. Marine animals
easily accommodate themselves to these enormous
pressures in the deep Their TISSUES being en-
tIrely permeated by fluids the pressure has little
no effect on them. Among all the various animals
dredged up from great depths it is only certain
kinds of fish which show any marked effects of the
alteration of pressure in coming to the surface Fish
with swimming badders suffer the most. They
come mp in the deep-sea dredge IN horribly dis
torted condition. with their eyes forced out of their
heads their bodies tightly stretched, and often all
their scales forced Off No sunlight penetates the
deep sea- Below 200 fathoms probably all is dark,
except perhaps in so far as light is given by phOs
phorescent animals. At the depth of 2 900 fathoms
and inward the temperature of the water Is never
many degrees above the freezing point. The waters
of the deep sea being everywhere dark and always
cold the conditions of life in them are the same all
over the world. Hence there no barriers to the
migratIons of animals in the deep sea- Time only
Is required for any deep-sea animal to roam from
any distant part of the globe to another. Marine
animals the author suggests, may through all time
have migrated in the course of generations across
the equator, from north to south, by way OF the
deep sea, and ON reaching temperate or cold latl-
tudes. may have worked their way up into shallow
water and taken to coast life, and assumed forms
more or less like those their ancestors who started
on the Journey. The geological results of tie deep
sea soundings have been a disappointment Pro-
fessor Agassiz had hoped to find almost all impor-
tapt fossil forms existing in life aud vigor at the
depths of the ocean. But this was not the case.
Large numbers of interesting new genera and
species of weIl-known families of animals have
been obtained by the dredge, but very few of them