SCIENTIFIC SUMMARY. 
343 
romorphce and Heteromorplice. By the latter term Professor Huxley pro- 
posed to designate the singular form OpistJiocomus, which recent exami- 
nation had convinced him must he arranged as a distinct group in the 
vicinity of the Alectoromorphce. — At the meeting on April 23, a com- 
munication was read from Mr. C. Spence Bate, F.R.S., on a new genus of 
freshwater prawns, proposed to be called Macrohrachium. Four new 
species of this group were also characterised, and named M. Americanum 
(from Guatemala), M. Formosense (from Formosa), M. Gangeticum (from 
Patna), and M. longidigitatum (from an unknown locality). Remarks were 
added, referring to the singular distribution of these allied species. — At the 
meeting held on March 26, Br. Murie read a paper on the supposed arrest 
of development of the Salmon {Salmo salar) when kept in fresh-water. 
Dr. Murie’s remarks were mainly based upon fishes hatched in the Society’s 
fish-house (from ova presented by Mr. F. Buckland) in January 1863 — one 
of which had recently died and another was still living. Mr. F. Buckland 
exhibited and made remarks on other specimens of Salmonoids reared in 
fresh-water. Dr. Gunther maintained that there was not sufiicient evidence 
to prove that the ova from which these fishes had been hatched, were 
really those of Salmo salar. Judging by the specimens themselves, he 
believed them to be more probably young of some species of lake trout, or 
hybrids between two different species of Salmo, 
The Nerve-cells in Fish. — Herr Stieda publishes, in Siebold and Kblli- 
ker’s Zeitschrift, a memoir on the above subject. In this the cells, both 
peripheral and central, are described as bodies furnished with a vesi- 
cular spherical nucleus, and usually also with a nucleolus. They have no 
cell-membrane, and are consequently to be regarded as simple masses of 
protoplasm, which presents a finely granular aspect. These cells differ in 
size and form, the latter depending upon the number of processes given off, 
and which vary in number from one to four or five. The processes are 
merely continuations of the granular cell-substance, and, so far as the 
author has seen, are never connected with the nucleus. He regards the 
apparently apolar cells as artificial products, and he has never noticed any 
division of the processes, nor any connection between one cell and another. 
Besides these true nerve-cells, the central nervous substance presents 
numerous minute cellular elements, whose nature is not quite determined, 
but which have been termed granules ” from their resemblance to the so- 
termed granules ” in the retina. The author, contrary to an opinion he 
formerly entertained, is now disposed, with Gerlach and others, to regard 
these bodies as a kind of nerve-cells.” — Vide Quarterly Journal of Micro- 
scopical Science, April. 
Good and Bad Silkworms’' Fggs. — M. Brouzet has described a method of 
separating the good eggs from the bad ones. The process consists in 
treating the eggs first with nitrate of silver, and then submitting the eggs 
to a species of testing, by trying their different densities in water. We 
should certainly doubt the practical applicability of the process. 
Butterfly Scales Characteristic of Sex. — We have received a copy of Mr. 
T. W. Wonfor’s recent paper on this subject. Mr. Wonfor’s observations 
are of great interest. We must refer our readers to the paper itself, pub- 
lished m the Transactions of the Brighton and Sussex Natural JEListory 
