-860 DR. W. B. CARPENTER ON TOMOPTERIS ONISCIFORMIS. 
among Heteropodous Mollusks. He would appear to have met with it only in its earlier 
phase; for his figure shows no more than twelve pairs of lateral appendages, without any 
caudal prolongation. | A | di 
It seems, however, to have been previously (?) observed by Quoy and Gaimard, who 
met with itin the Bay of Gibraltar during the voyage of the * Astrolabe;' but as their 
account of it was first published in 1827 (Annales des Sciences Naturelles, tom. x. p. 235), 
the name Briarea scolopendra, by which they designated it, must yield in priority to that 
of Eschscholtz. The specimen which they describe as having been taken in the Bay of 
Gibraltar, is stated to have attained a length of 4inches. If there be no error in this - 
description, it must have been far larger than any that has been elsewhere met with. 
They speak of it as possessing 24 or 25 pairs of lateral appendages or fin-feet ; of these, - 
however, their figure shows only 21 pairs, of which 17 belong to the body, and 4 to the 
caudal prolongation. If this figure (which strikes me as in many respects rather an 
ideal diagram than a true representation) approaches in any degree to the real propor- 
tions of their specimen, its lateral appendages must have been very much longer than 
those figured by any of the other naturalists who have described it, their maximum 
length being in the anterior portion of the body, and a progressive diminution taking 
place as far as the commencement of the caudal prolongation, behind which they are 
merely rudimentary. Thus the outside contour of the entire animal is not very dissimilar 
to that of a boy's kite, the caudal prolongation representing the tail. It is somewhat 
singular, that, notwithstanding the extreme transparency of this animal, MM. Quoy and 
Gaimard were unable to make out its alimentary canal, although they described and 
figured what they believed to be ova. They considered Briarea to be a Mollusk, nearly 
allied to Glaucus: 
In Müller’s Archiv for 1847, there are a description and a figure of Tomopteris onisci- 
Jormis by Busch, who met with it in the North Sea. This figure nearly corresponds, 
_ except in the proportional shortness of the lateral appendages, with that of MM. Quoy — 
and Gaimard. The number of these appendages which Busch represents is 18 pairs, the 
form of all being the same, and their size diminishing gradually from the 1st pair to 
the 18th, which is close to the posterior extremity of the body, there being no distinct — 
caudal prolongation. Busch described and figured the ova in the perivisceral cavity, 3$ —— 
Professor Huxley has done subsequently ; and he also noticed other bodies which seem = 
to correspond with what Professor Huxley regarded as bundles of spermatozoa. We 
In the sueceeding volume of the same Journal (1848) is a very elaborate memoir by 
Grube on Tomopteris, based on specimens collected by Krohn (probably in the Medi- 
terranean), and preserved in the Museum of St. Petersburg. This memoir is specially 
devoted to the description of some of the minutest details of the structure of the animal, 
and to the inquiry into its place in the zoological scale. Grube’s figure of the entireanimal — 
IS not only small in scale, but is somewhat rudely sketched ; it represents twenty pairs of ; e 
lateral appendages, and a caudal prolongation of cylindrical form, apparently without * 
any appendages at all. In his description, however, the author speaks of this caudal pro- — 
longation as bearing rudimentary fins, in the form of whitish protuberances; these, Él 
remarks, are as yet undivided ; whilst the fully-developed appendages of the anterior part — 
