1889.] California Food Fishes. 109 
in great numbers during December and January. The eggs 
are very adhesive when first deposited, but half an hour after 
deposition they lose their stickiness and remain free when 
loosened. The yolk is collected in spherical masses. The pro- 
toplasm is yellow, and the formation of the germinal disk can 
readily be watched. Strands of the protoplasm can be seen 
extending from it into the yolk. The first cleavage furrow is 
formed about two hours after fertilization, and the first cleav- 
age occupies about forty-five minutes. The furrow travels 
slowly towards the base of the germinal disk, which it reaches 
in about twenty-eight minutes ; at this stage the two newly 
formed cells seem well separated. As soon as the furrow has 
reached the base of the disk it begins to retreat, leaving but a 
line to separate the two cells. When the furrow has entirely 
retreated, the division of the two cells is not very plain, and the 
second furrow is immediately formed. The division of the disk 
into four cells is more rapid than its division into two. The 
further development very much resembles that of the shad as 
it is described by Ryder; it is, however, much slower. The 
blastopore closes about thirty hours after segmentation. The 
heart is formed near the close of the second day. Kupfer's 
vesicle appears about fifty hours after fertilization. On the 
sixth day one shell was found, but the escaped fish could not be 
seen. Other embroyos continued to be active in the shell 
five days longer, when they died. 
The Smelt of California, Atherinopsis calif orniensis, is one of 
the most abundant of the food fishes. It enters San Diego bay 
m December to spawn. The eggs are large and transparent, 
and, during the earlier stages of development the oil is distri- 
buted in a number of globules, while in a later stage but a single 
oil globule is present. Each egg is provided with about ten 
long filaments which differ somewhat from those of Fundulus. 
The base of each filament is enlarged, disk-shaped and appar- 
ently hollow, and the substance of the zona seems to enter it. 
The filaments are uniformly distributed over the surface of the 
^g^, and in the ovary they are coiled around the Qgg in one 
