1893.] NATURAL SCIENCES OF PHILADELPHIA. 89 



or in the long-bodied, double-tailed races. This increase in the 

 length of the intestine is also indicated by the very protuberant 

 abdomen of the short-bodied race. This short-bodied race, with a 

 protuberant abdomen, I am informed by breeders, is a very vora- 

 cious feeder, thus not belying the indications of its large abdomen 

 and proportionally long intestine. 



It is also probable that the bodies of the vertebra? are shorter in 

 the short-bodied than in the long-bodied races. This point I have, 

 however, neglected to determine. 



I believe, in short, that the degenerative changes in the muscular 

 system of the Japanese Gold-fishes is connected with their continued 

 restraint to small aquaria for many generations, and that their mus- 

 cular system has degenerated through disuse. That, on the other 

 hand, the failure to be able to expend energy in the production of 

 motion of the body in the water has reacted in other ways upon 

 their organization, and especially upon the growth of the fins. This 

 has gone on until, in some of the races, it would actually be possible 

 to envelop almost the entire head and body in the enormous double 

 caudal. In fact, these members grow so long that they become an 

 actual hindrance to rapid swimming, and are of less use in pro- 

 pelling the fish in the water, so that their swimming becomes very 

 slow, and seemingly performed with some difficulty as compared 

 with the normal form. All the fins partake of this tendency to 

 become extended ; the pectorals enlarge and lengthen, and the 

 dorsal, in some races, becomes so long that it falls over and over- 

 hangs one side of the body. Fish-culturists also tell me that it is 

 useless to try to keep these races with other species of fishes in 

 ponds, because the more active carnivorous forms will soon bite off 

 and destroy the long, graceful, and lace-like caudals of these help- 

 lessly modified Japanese races. These races have been so modified 

 by man's agency, that they have become absolutely unfitted to suc- 

 cessfully battle for existence, if left to themselves. 



Their sluggish habits have been purposely cultivated by Oriental 

 fish-fanciers. To such an extreme of sluggishness have they been 

 brought, that, owing to their monstrous development, they are some- 

 times no longer able to maintain their equilibrium in the water, but 

 stand on the head or tail in the very small aquaria, in which they 

 are kept, and in which they would become asphyxiated were it not 

 for the precaution taken by the Japanese to introduce into the same 

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