EIGENMANN— TROGLOGLANIS PATTERSONI. 



399 



noctiirnus has been found in the springs (mouth of the underground 

 river) at San Marcos and at various other places in Texas and is the 

 only species of the genus recorded from Texas. Schilheodes noc- 

 ttirhiis is, however, not closely related to the blind catfish living in 

 the underground rivers of the same region. 



I have called attention to the fact that the species living in the 

 caves of the south are more intimately adapted to their subterranean 

 home than those of the north. The eyes of the Texan Typhlomolge 

 are more degenerate than those of the salamanders of Missouri. 

 Judging from external appearance the eyes of the Texan Troglo- 

 glanis are more degenerate than those of any of the blind fishes from 

 farther north. The technical description of Trogloglanis follows : 



Fig. 2. Outlines of the head as seen from above. 



Head similar to that of a tadpole, as broad as long; mouth in- 

 ferior; teeth?; adipose fin long and low, rounded posteriorly, con- 

 nected at its base with the accessory caudal rays ; no external evi- 

 dence of eyes; distance between origin of dorsal and tip of snout 

 half as great as origin of dorsal from the end of the adipose; dis- 

 tance between snout and origin of ventrals i% in the distance between 

 origin of ventrals and base of middle caudal rays; pectoral spine 

 strong and pointed, about two thirds as long as the longest ray, about 

 equal to the length of the head behind the posterior nares, smooth in 



