Conh ibutions from the San Diego Biological Laboratory, //j 



Oligocottus analis Girard inhabits rocky pools on the 

 ocean beaches about San Diego. Its eggs, hke those of many 

 other cottoicls, are ghied together as they are extruded from the 

 ovarian duct. The spawning period of this species probably ex- 

 tends from January to April. The *i'^'^ measures 1.2 mm., is of 

 a brownish-yellow color and has one large, and from five to nine 

 smaller oil globules. The Q'g<^ 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 AGCJREG.vTU.s GiBBOXS. — 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 lood is not 

 needed in the '^'^i^'g., and that the eggs are consequently reduced 

 to a minimum size. The comparatively frequent {presence of the 

 larger eggs suggests that they are a reversion to a condition when 

 these fishes were oviparous and required more yolk. The nucleus 

 in the larger eggs does not ditier in size from that of the smaller, 

 the increase in size being entirely restricted to the food portion of 

 the ^^^. another fact tending to prove that the smaller eggs have 

 been reduced from formerly larger eggs. 



Stoi.ephorus. — 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 8 to 4, and as 8 to 5. 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 



