Putnam.] 224 [December 2, 



The peculiar and marked characters of the family left no doubt as to 

 all four of the species belonging to it; for the smooth body, caused 

 by the deeply imbedded and small circular scales, the shape of the 

 body, and the blunt, flattened head, the position of the fins, and the 

 absence of the ventral fins in Typhlichthys and Chologaster, the 

 large air bladder slightly divided longitudinally, the single ovary, the 

 peculiar shape of the liver, the marked character of the general 

 structure of the intestinal canal with its external termination in front 

 of the pectoral fins, and the agreement of all in the development and 

 shape of the lobes of the brain, were all characters that could not 

 mislead in bringing the three genera into a most natural and well- 

 defined group, whatever its allies may be. 



Mr. Putnam then alluded to the habits of the three species of the 

 family. (Heteropygii) found in the cave, and showed that what had 

 been stated regarding the habits of the blind fishes, which, from be- 

 ing surface swimmers, had been considered as better adapted for life 

 in the subterranean waters than would otherwise be the case, no 

 longer held good now that we know the habits of the Chologaster 

 are just the contrary ; as they seldom leave the bottom of the stream, 

 and yet evidently thrive as well as their white cousins at the sur- 

 face of the same waters. Then, as regards color, and its supposed 

 absence in the cave, he thought that the specimens on the table were 

 evidence that much had been said on that subject without a full 

 knowledge of the facts; for the specimens proved, beyond question, 

 that light is not necessary for the production or maintenance of 

 color. Darkness did not bring about atrophy of the eyes, if the 

 specimens exhibited were any test, for here we had fishes with eyes 

 which had (for all we know to the contrary) been in the cave as long 

 as those species without them, and were as essentially subterranean 

 forms, so far as our present knowledge goes; for we have no right to 

 assume that the five specimens of Chologaster obtained were any 

 later inhabitants of the cave than the blind fishes, until at least one 

 specimen of the former had been collected in the outer waters of the 

 vicinity of the caves; and he had carefully seined the Green River 

 and many of its tributaries without finding it. 



He also called attention to the fact that if the theory of develop- 

 ment of the blind fishes from the Chologaster was maintained, it was 

 not only necessary to account for the atrophy of the visual organs, 

 the development of the tactile organs with which the blind fishes 

 were provided, and the loss of coloration which characterized them; 



