A REVISION OF THE CAVE FISHES OF NORTH AMERICA. 



By Ulysses O. Cox, 

 Professor of Biology, Staie Normal School, Manhato, Minn. 



This paper '^ deals with the taxonomic characters, the synonym}^ and 

 distribution of the members of the Amblj'opsidffi, a small group of fishes 

 confined to the central and southeastern portions of the United States, 

 apparently entering caves wherever caves exist within the limits of 

 their distribution. They are the cave fishes par excellence of North 

 America. Their relationships are with the Umbrida? or mud-minnows 

 and the pikes and killi- fishes, and may be expressed by the following 

 key to the families of the Haplomi, modified from Jordan and Ever- 

 mann's Fishes of North and Middle America: 



a. Lateral margin of the upper jaw formed by the maxillaries, premaxillaries not 

 protractile; vent normal. 



h. Jaws depressed and produced, basis of cranium double Esocklse. 



bb. Jaws not produced Vmbridie. 



aa. Lateral margin of the upper jaw formed by the premaxillaries; basis of cranium 

 simple. 

 c. Vent close behind the isthmus; premaxillaries little Tprotvactile . . AmbJyopsidse. 

 cc. A'ent in normal position; premaxillaries extremely protractile Pa'ciliidse. 



Several characters tliat have heretofore been used to distinguish the 

 genera of the Amblyopsida} have been examined in detail— name!}", 

 the character and distribution of the tactile ridges and the number of 

 the p3doric coeca. 



Tactile ridges. — While the tactile ridges peculiar to this family are 

 undoubtedly better developed in the blind members of the famih^ than 

 in CJiologaster, the difference is one of degree only. The same is true 

 of the differences between the different species of Chologaster. In 

 this genus they are best developed in C. papllliferus.^ and in this spe- 

 cies they are better developed about the snout than elsewhere. A 

 detailed comparison of the ridges of the head in the different species 



«This paper has been prepared under the direction of Dr. Carl H. Eigenmann, who 

 has furnished the material and literature for the work and given invaluable assist- 

 ance. Cut 8 is by Mr. Thomas Large; pi. i and figs. 9 to 11, pi. ii, are by Doctor 

 Eigenmann and the author, figs. 4 to 6, pi. ii; fig. 1, \)\. iv; fig. 2, pi. v; and pi. vi 

 by Doctor Eigenmann; pi. iii from photographs made by Dr. D. W. Dennis; cut 22 

 is copied from the Proceedings of the U. S. National Museum for 1888, p. 168, and 

 the remaining figures are by the author. 



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