136 FISH HATCHING. 



contents of the umbilical vesicle into the 

 body of the fish, the one decreasing as the 

 other increases as well as the curious phe- 

 nomenon of this vesicle having a double 

 covering ; secondly, the perpetual motion of 

 the pectoral fins. I therefore requested my 

 friend, Mr. Henry Hancock, F.Z.S., F.C.S., 

 &c., to undertake a microscopic examina- 

 tion of them, and this gentleman has kindly 

 sent me for publication the following inte- 

 resting and able paper on the subject, in 

 which several new and important facts are 

 elucidated. 



SOME REMARKS RELATIVE TO YOUNG SALMON". 

 BY HENRY J. B. HANCOCK, F.Z.S., F.C.S. 



In January of this present year, it was 

 suggested to the author that he should inves- 



