58 : General Notes. [ January, 
completely successful. The young are now eight days old, and 
are thriving wonderfully. I labor under a great many inconveni- 
ences, and against many obstacles, having only a couple of fruit 
jars to hold the animals, and a very poor little microscope, but it 
is sufficiently powerful to enable one to trace the course of de- 
velopment in a general way, and that I have done. 
“ Of course I have a good many other duties, and since our 
arrival here I have been trying to find out some things about the 
sub-current in the Straits, consequently I could not give the 
oysters all the attention I desired, but I have followed them 
through each step as nearly as possible, and they have been 
exactly as you have figured for the American animal. I have 
seen them assume the form of each figure or set of figures! suc- 
cessively, and they are now about as your last figures show them. 
I shall watch them as closely as possible henceforward, though 
the necessity for transferring them to a larger vessel, may prevent 
my continuing the observations, and as we sail to-morrow, a gale 
of wind may send my young brood afloat again in the briny 
ocean. I think my success is due to the uniform temperature of 
my room where I have kept the jars. Though I have not 
registered it, yet it must be nearly the same at all times, for I am 
personally aware that the atmosphere is rarely changed in any 
way. The brood is the offspring of two males and two females, 
and the whole lot which I examined appeared exactly as did 
those we are familiar with. The adults came from the waters of 
Cadiz bay, and are natives. 
“So far as these results go, they prove that the artificial propa- 
gation of the European oyster is practicable to just the same 
extent as our own, and I think that it throws grave doubts upon ~ 
the theory that the embryo is protected within the shell, and that 
the impregnation of the ova occurs there and nowhere else. 
“Tam quite elated over my success, and thought that probably 
it would interest you, and therefore have written. I have made 
but one deviation from your method, and that was in the supply- 
ing of water. I have given but very little new water, rarely a gill 3 
and a halfa day. I am very truly yours, FRANcIs WINSLOW.” 
CHANGE IN THE NeERvous SystEM OF BEETLES DURING META- 
Mee oes cE a a 
mann’s researches on the flesh fly. Michels concludes that the 
separate ganglia of the ventral cord of the pupa and imago are — 
formed during metamorphosis from the larval stage, not de ov, 
*See Prof. W. K. Brook’s, the Development of the Oyster. Studies from the Bio- 
logical Laboratory of Johns Hopkins University.—Zds, 
