116 



ation of Etheostoma caprodes. In the form of the body and the colora- 

 tion it could more easily fall within the range of variation of Etheostoma 

 aspro. Indeed, this affinity is so strong that if it is merely a variation 

 it can only have come from Etheostoma aspro. 



Both in coloration and in structural characters it can readily be dis- 

 tinguished from either of the two most closely related species, so that it 

 would be easy enough to characterize it as a new species. The reasons 

 against this are the usual ones, namely, that we have only a single speci- 

 men and that if it represented a species that is even only poorly established 

 more specimens should have been obtained in the enormous amount of 

 seining that was done during the same, previous and subsequent summers. 



It is entirely possible that we have here a hybrid. There are charac- 

 ters that show a strong affinity for each of the supposed parent species, 

 as well as characters (scales) that are intermediate. Both parent si>ecies 

 occur in the lake, Etheostoma caprodes abundantly, Etheostoma aspro spar- 

 ingly. The most serious objections against considering this a hybrid is 

 the large number of dorsal spines— sixteen— in the dorsal, larger than in 

 either parent species. About 2 per cent., however, of Etheostoma caprodes 

 have sixteen spines in this lake and an occasional specimen is found with 

 seventeen. It should be stated in this connection that I have experi- 

 mentally obtained healthy fiy between Etheostoma coeruleum and Etheos- 

 toma nigrvm, two species much more distinct than the assumed parent 

 species. There seems, therefore, to be considerable evidence in favor of 

 the assumption that this is a hybrid. 



