BAIRD.TKTJ,A CHRYSURA AND ANCHOVIA MITCHILLI. 



17 



very slowly. Nor do they undergo any material changes in form or appearance. They 

 are relatively long and slender and highly transparent. At 36 hours after hatching 

 (fig. 39) the mouth is apparently functional and soon begins to show the form character- 



-j?/. 



hp^- 



ANCHOVIA MITCHILU. 



Fig. 33. — Egg showing blastodenn spreading over 

 yolk; QT, germ ring, X 60. 



Fig. 34. — Egg showing blastopore nearly 

 closed; hp, blastopore; gr, germ ring, 

 X60. 



istic of anchovies. The maxillaries are comparatively long. The lower jaw is long and 

 narrow. The tip of the head, however, does not as yet extend forward beyond the mouth. 



ANCHOVIA Mircmiii, 

 Fig. 35- — Egg with embryo showing 18 to 20 somites; Fig. 36,— Egg with advanced embr^-o, X 60. 



Kii, Kupffer's vesicle. X 60. 



The critical period for the larvae of this species begins before the close of the second 

 day after hatching. When kept in dishes of sea water many of them died before reaching 

 the third day. Observations ^ ..._ 



on the later larval develop- ..f^ ■ .- '~^i>":,. 



ment were made on larval 

 fishes collected in the stow 

 net. 



Larval fishes 3 to 4 mm. 

 in length (fig. 41) do not differ 

 markedly in appearance from 

 larvae in which the yolk sac is just absorbed. They retain the same general form 

 and remain almost perfectly transparent. The fin folds remain continuous. Their 

 relative depth, however, has materially decreased. 



Fig. 37. — Anchovia mitchilli newly hatched, actual length 1,9 mm. 



