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172 FISHES OF SAN DIEGO—EIGENMANN. 
Ripe females were found March 27. The majority of the females were 
not ripe and the spawning time may be placed as April. 
The eggs are quite remarkable in their structure and coloration. To 
the unaided eye they appear opaque, of a purplish pink color inside of 
which is a spot of brownish red and upon it a dot of opaque white. 
The greater portion of the egg is covered by a thin transparent mem- 
brane but at one portion there is a large opaque cushion by which the 
egg fastens itself to foreign bodies. When fastened the egg becomes 
depressed. The longer axis measures 825, the shorter 562. The diain- 
eter of the cushiony cap is 975u. This cap on sections of the ovary 
and of the ripe eggs is seen to be composed of innumerable very fine 
filaments, the tips of which are swollen and club-shaped. Their small 
size, the great number and their aggregation at one pole of the egg 
render their filaments different from all the other appendages of fish 
eggs yet described. 
The yolk is composed of rather large spheres. On its upper surface . 
are imbedded several pale yellow oil globules and about an equal num- 
ber of bright purple oil globules (black in Fig. 16, pl. x.) In the middle 
of these is a larger white body the function of which is not known. 
Younger ovarian eggs 0.625 millimeters in diameter are entirely com- — 
posed of purple spheres while still younger ones are colorless. 
The germinal disk is always formed beneath the cap of filaments regard- 
less of the position of the cap whether at the side, above, or below. This 
fact renders the early stages in the development obscure. The germi- 
nal disk is seen in Fig.16. The first segmentation is completed in about 
ten hours after fertilization and results in two elongate cells whose longer 
axes lie parallel, Fig. 17. After fifteen and a half hours eight cells 
were observed. In this egg in which the cap was placed above, the oil 
globules and white disk appeared to lie below the germinal cells, a fact 
which would indicate that the oil globules were mobile in the yolk and 
tended to lie at the top. The oil globules therefore have, in this case, 
no influence on the position of the germ. Further stages in the seg- 
mentation of the germinal disk could not be observed. 
The next stage which could be satisfactorily observed was one hun- 
dred and thirty-two hours old. It is represented in Fig. 19. The eyes 
at this time are well along in their development. The embryo embraces 
about half of the yolk and seems to be composed of large cells perfectly — 
transparent. The purple oil globules (not figured) occupy the center | 
of the field while the white body lies directly beneath the tail. Several 
black pigment cells have been found and lie on the yolk. The yellow 
oil globules still remain arranged about the white body. 
On the seventh day the heart beats slowly. The pigment spots on the 
surface of the egg have greatly increased in number. It was now — 
observed that the position of the embryos at this stage are independ- | 
ent of the opaque cap. 
