Contributions from the San Diego Biological Laboratory. 45 
OLIGOCOTTUS ANALIS GIRARD inhabits rocky pools on the 
ocean beaches about San Diego. Its eggs, hke those of many 
other cottoids, are glued together as they are extruded from the 
ovarian duct. The spawning period of this species probably ex- 
tends from January to April. The egg measures 1.2 mm., is of 
a brownish-yellow color and has one large, and from five to nine 
smaller oil globules. The egg is surrounded by a thick zona, 
which appears to be perforated by two sets of canals—the usual 
fine ones and fewer, much coarser canals. In optical section, the 
latter appear as black lines. The eggs hatched in from eighteen 
to twenty-four days, under seemingly identical conditions. The 
following peculiar pigmentation distinguishes this. species on 
hatching; a pigment cell above each eye, that over the left eye 
always larger; a group of pigment cells on the nape, the upper 
two being somewhat removed from the rest, a broad black shield 
of pigment cells overlying the body cavity; about thirty-four pig- 
ment cells along the lower margin of the tail. 
MICROMETRUS AGGREGATUS GIBBONS.—In dissecting the ova- 
ries of this species, nodules in the ovarian stroma, were repeat- 
edly observed, which were much larger than the ripe eggs of 2m 
m. diameter. On sectioning these nodules, they were found to 
be eggs, much larger than the normal size, measuring .5 mm. in 
diameter. From the fact that the young of these fishes remain 
in the ovary from four to five months and are abundantly sup- 
plied with food from the time of hatching to the time of leaving 
the ovary, it may be inferred that a great amount of food is not 
needed in the egg, and that the eggs are consequently reduced 
toa minimum size. The comparatively frequent presence of the 
larger eggs suggests that they area reversion to a condition when 
these fishes were oviparous and required more yolk. The nucleus 
in the larger eggs does not differ in size from that of the smaller, 
the increase in size being entirely restricted to the food portion of 
the egg. another fact tending to prove that the smaller eggs have 
been reduced from formerly larger eggs. 
STOLEPHORUs.—There are three species of this genus found 
in San Diego Bay; ringens, compressus and delicatissimus. In 
May, great numbers of Stolephori which are probably the young 
of ringens, are swarming in the bay and are especially abundant 
near the wharf of the Pacific Coast S. S. Company, the eggs of the 
first and last of these species are oval in shape and pelagic. Slightly 
oval pelagic eggs have been recorded before, but none in which 
the longer axis is so strikingly greater than the shorter. We 
have detected three sizes, having the longer axis to the shorter 
as 7 to 5, as 8to 4, and as 8to5. As variations between the 
last two are found in great abundance, they probably are identi- 
cal. The germ for obviously mechanical reasons always collects 
at one end of the longer axis, most probably the micropylar end. 
If this is so, these eggs will serve well to study the relation of the 
