JANUARY 4, 1884.] 
The pedunculated lateral-line organs of Gas- 
trostomus. 
The recent discovery of a form of deep-sea fishes 
closely allied to the Eurypharynx described by M. 
Vaillant, by the U.S. fish-commission steamer AI- 
batross, has afforded excellent opportunities for a 
more thorough examination of the external charac- 
ters presented by the skin of these forms. This 
species of eurypharyngoid fishes, — the one studied 
by Professor Theodore Gill and myself, and named 
by us Gastrostomus Bairdii, — upon closer examina-. 
tion of the region of the lateral line, discloses features 
which appear to be somewhat remarkable, if not 
unique, amongst organs of the kind hitherto known. 
The lateral line is in its usual position, and begins 
just behind the head. There is no mucous canal 
covering the end-organs; but these are isolated in 
groups of from two to five, standing on the skin in an — 
oblique row at the hind 
margin of each muscular 
somite. The groups con- 
sist, in fact, of from two 
to five stalked organs, as 
shown in fig. 1 in the cut. 
The stalks are not pig- 
mented at all, except at 
the tips, where they sup- 
port a discoidal cup- 
shaped organ, which is 
more or less completely 
pigmented internally. In 
some instances these end- 
organs are very distinctly 
cup-shaped; in others 
that form is less clearly 
apparent. The base from 
which the stalks arise is 
not so deeply pigmented as the surrounding skin, 
Fie. 1. 
which is very densely loaded with pigment, and very | 
black. The pigment on the basal disks is, in fact, 
arranged in a slightly reticular manner: the pig- 
mented layer is continuous with the outer clear 
sheaths of the stalks; and the medullary portion of 
the stalk can be seen in some cases to consist mainly 
of nerve-fibrils, which pass outwards to the cup-like 
organs at the tip. In afew cases there appears to 
be a clear space in the centre of the cup-like end- 
organ, as shown in fig. 2, surrounded by a dense 
circle of pigmented tissue. ¢ 
The function of these side-organs of Gastrostomus 
is apparently tactile, or may serve a special purpose 
at the great depth in which this fish lives. ‘They re- 
mind one very forcibly of the rows of comb-like end- 
- organs which have recently been described by F. 
Leydig on the head of the cave-fish 
(Amblyopsis spelaeus DeK.); but in 
this case the stalks are not so robust, 
and are much more slender, and 
relatively longer. It may even be 
that these lateral bands of side-or- 
gans of Gastrostomus are phospho- 
rescent at their tips, like the side- 
organs of scopelids, steroptychids, 
etc. The lateral bands made up of short oblique 
rows of these organs, as the fish moves through the 
water at a depth of five to fifteen hundred fathoms, 
may possibly become luminous. 
That they are also sensory in function there can 
be no doubt, being found in the usual position of the 
lateral line, as in common fishes, and, like it, prob- 
ably innervated from the vagus. The stalks are 
fully a sixteenth of an inch long, and are apparent 
SCIENCE. 5 
on the side when the fish is immersed in alcohol or 
water, and project outwards quite freely, so as to be 
visible along the sides when the fish is viewed from 
above. These naked side-organs remind one also 
somewhat of the naked nerve-hills on the sides of the 
body of young fishes, such as those of Gadus and 
Gambusia. In the former the stiff sensory hairs of 
the nerve-hills project immediately from the surface 
of the hill into the surrounding water, but in no em- 
bryo fishes am I aware that the side-organs are ever 
pedunculated. In fact, the side-organs of Gastros- 
tomus Bairdii, like the whole of the rest of the orga- 
nization of the animal, particularly its skull and 
branchial apparatus, present an extreme phase of 
specialization. J. A. RYDER. 
RETROSPECT AND PROSPECT. 
Wire the present number Science enters 
upon the second year of its existence. The 
time is an appropriate one, while extending a 
cordial greeting to its readers, to call their at- 
tention to its work and its purposes. That a 
journal of popular science, with the varied and 
informal contents appropriate to a weekly pub- 
lication, would, if judiciously conducted, prove 
a welcome addition to the list of American 
periodicals, has long been felt by those most 
interested in scientific progress; but, when 
the numberless difficulties in the way of suc- 
cess had to be considered in detail, they were 
found to be numerous and perplexing. The 
general scope of the journal was the only fea- 
ture about which little doubt could be felt. 
Two quite distinct yet inseparable objects of 
existence presented themselves: one was to 
keep the readers of the journal informed of 
the progress of science in all its branches; the 
other, to give expression to the well-matured 
views of scientific men upon all public questions 
connected with the increase of knowledge, and 
thus to become, so far as possible, an organ 
of public opinion upon scientific affairs. 
In pursuing the latter object the path of 
duty was too plain to require discussion. The 
journal must be the organ of no individual, 
clique, or party, but must, while preserving 
entire impartiality, give plain and fearless 
expression to its convictions upon any question 
in which the interests of science at large were 
involved. How far it has fulfilled this require- 
ment is a question to be decided by its readers 
and patrons, without argument from ourselves. 
The question of the contents of the journal 
in detail was a far more intricate one. Shall 
its articles be designed exclusively for the spe- 
cialist, or shall the results it makes known be 
popularized by the omission of all purely tech- 
nical nomenclature? Shall they be long and 
elaborate, or short at the risk of incomplete- 
ness’ Shall they be strictly and purely scien- 
