L BIOLOGICAL SOCIETY OF WASHINGTON. 



trol and management for large enterprises, involving large outlays 

 of money, is the only policy which can be successfully carried out. 



Mr. C. W. Smiley stated that, in spite of shad-hatching having 

 been prosecuted with increasing vigor annually since 1874, the 

 number brought into the Washington market had decreased from 

 521,36s in 1881, to 350,292 in 1882, and 261,474 in 1883. But for 

 fish-culture the decrease would have been enormously greater. He 

 affirmed that we are yet ignorant of many essential elements of 

 fish propagation, and only the highest scientific ability can discover 

 them. 



Dr. T. H. Bean, referring to Mr. Smiley' s statement, said that it 

 was manifestly unfair that fish-culture should be expected to do 

 more than nature could do in keeping up the supply of fish in any 

 body of water ; that there were many things for the fish-culturist 

 to do besides the planting of young fish ; that the pollution of 

 streams and the artificial obstructions, such as dams, must first be 

 removed, and that in interpreting the results of fish-culture, ques- 

 tions of temperature, freshets, and other natural disturbances of 

 ordinary conditions upon the breeding grounds of fishes, should be 

 taken into account. 



Dr. T. H. Bean exhibited a specimen of pipe-fish, Sipliostoma, 

 sp., which showed an augmented development of fins, the super- 

 numerary fin being post-anal, and much more developed than 

 the ordinary rudimentary anal of the male Siphostoma. In size and 

 general appearance it resembled more nearly a caudal fin, but from 

 its position it must be called post-anal. In the Lophobranchiates 

 he believed that the vertical fins are not developed from an embry- 

 onic fin-fold, as is the case in most fishes. This example was to be 

 considered as an illustration of a reversion to a former condition 

 of fishes of this type, in which they did possess at one stage of 

 their existence an embryonic fin-fold, 



Mr. Ryder remarked that the specimen oi Siphostoma with super- 

 numerary anal fin was certainly an example of the restoration 

 towards the ancestral form. Its presence might be explained on the 

 supposition that the fin-fold, which is continuous in ' the embryo, 

 had been exaggerated into development at this particular i)oint, 

 and mesoblastic tissue thrust out in the process of development into 

 the fold itself, thus furnishing the rudiments upon which there was 



