BAIRDTELLA CHRYSURA AND ANCHOVIA MITCHILU. 



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?/. 



ANCHOVIA MlTCHILtl. 



Fig. 33. — Egg showing blastoderm spreading over i'lG. 34. — Egg showing blastopore nearly 



yolk; QT, germ ring. X 60. closed; bp, blastopore; qt, 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 MITCHU.LI. 



Fig. 35. — Egg with embryo showing iS to 20 somites; FiG. 36. — Egg with advanced embr>'o. X 60. 



Kv, Kupffer's vesicle. X 60. 



The critical period for the larvse 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 larv^al develop- 

 ment were made on lar^^al ^s^ r^ Vt^''--^— ^'I('*^^^^'^^^5^^:^^liii!£iS^^ "\ 

 fishes collected in the stow ^j^ySV 9s_!P7'^"X^l^^?^^^^^X°^ J 

 net. ' ^ 



Larval fishes 3 to 4 mm. 

 in length (fig. 41) do not differ 

 markedly in appearance from 

 larvse 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. 



