EGGS AND LARV^ OF TELEOSTEANS. 129 



tains an oil globule '15 mm. in diameter. The ova are suspended separately in 

 the water not united in masses. The dimensions of the newly-hatched larva 

 are 1*77 mm. in total length, 15 mm. from the yolk sac to the anus. 



The ova of Grenilabras, of which genus Hoffmann examined four species, 

 are not pelagic, but adhesive. The zona radiata shows the division into two 

 layers, which occurs in most adhesive ova. The diameter of the ovum is *7 to 

 "75 mm. The yolk is not homogeneous, but contains a number of vitelline 

 globules ; there seem to be no oil globules. The newly-hatched larva is 

 3*6 mm. long, and the anus is "6 mm. from the yolk sac. 



Thus we see that considerable variations occur in the family of Labridse in 

 the character of the ova. Most of the genera produce pelagic ova, but the ova 

 of Crenilabrus are adhesive. As in the Gadidse, there is either a single oil 

 globule in the yolk or none at all. Two characters seem constant throughout 

 the family — (1) that the notochord is multicolumnar, (2) that the anus is at 

 some little distance from the yolk sac, though not nearly so far back as on the 

 Physostomi. The separation of rectum and yolk sac occurs also in the Carangidae 

 (Te?nnodon),&nd among the Physoclisti seems to be confined to these two families. 



Fam. 3. Embiotocid^e. 



Fishes of the North Pacific, most abundant on the American coast. 

 All viviparous. 



Fam. 4. Chromides. 



Order V. LOPHOBRANCHII. 



Fam. 1. Solenostomid^e. 



According to Gunther, the female bears the eggs attached to filaments 

 developed on the ventral fins, the inner edges of which are united to the skin of 

 the body. 



Fam. 2. Syngnathid^e. 



In Siphonostoma typhle, which is common on the British coasts, the ova are 

 carried till the time of hatching by the male in a pouch formed by longitudinal 

 folds of the skin behind the anus. 



In Syngnathus there is a similar pouch in the male. According to Ryder, 

 yolk contains numerous oil globules. 



In Nerophis the ova are attached to the abdomen of the male by a viscid 

 secretion in front of the anus. N. lumbricAformis and N. aquoreus are not un- 

 common on the east coast of Scotland, but I have not had an opportunity of 

 examining the ova of either. 



Some account of the development of Hippocampus is given by John 

 A. Ryder in Bull. U.S. Fish. Commission, Bd. 1. In the embryonic Hippo- 

 cumpus the fin-fold is wanting, in Syngnathus it is but slightly developed. 



VOL. XXXIII. PART I. R 



