i8 



BULLETIN OP THE BUREAU OF FISHERIES. 



Fishes 5 mm. in length (fig. 42) illustrate an early stage in the differentiation of the 

 dorsal and the anal fins. In larvae of this size the posterior region of the intestine is 

 already convoluted. In lateral view these convolutions have the appearance of vertical 

 folds. This character is apparent externally until the little fishes have attained a length 

 of 15 to 20 mm. 



In fishes 7 to 8 mm. in length (fig. 43) the dorsal and anal fins are becoming 

 definitely outlined. In some instances the full number of fin rays is already present. 



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Fig. 38. — Larval fish 12 hours after hatching, actual length 2.7 mm. 



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Fig. 39. — Larval fish 36 hours after hatching, actual length 2.9 mm. 





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Fig. 40. — Larval fish 3 days after hatching, actual length 2.7 mm. 



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Fig. 41. — Larval fish 3.4 mm. in length. 



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Fig. 42, — Larval fish 5 mm. in length. 



iNCHO\TA MITCHILLI. 



A few small darkly pigmented areas are now apparent along the ventral margin of the 

 body in the thoracic region and at the base of the anal fin. 



As the young fishes grow larger they become less transparent, but show very little 

 pigment. They undergo no marked changes in form, but gradually assume the appear- 

 ance of adult fishes, showing all the diagnostic characters of the species. The silvery, 

 longitudinal band characteristic of adult anchovies, however, does not appear until 

 the young fishes have attained a considerable size. 



