127 



of the intercalarium are more slender in P. ore as (TS 181[1]) than in other species of the 

 genus (TS 181 [0] ). 



In the outgroups. the dorsal margin of the intercalarium is slightly concave, and all three 

 parts of the bone are moderately broad. 



The tripus (Figs.77A-C. 79A-E. 80A) is the largest element among the Weberian ossicle, 

 and is located at the posterior portion of the bony chain formed by the ossicle. Three parts 

 can be recognized for this triangular bone: anterior, medial, and posterior ramus. The an- 

 terior ramus extends and connects with ventral end of the intercalarium"s main part via 

 ligament. The medial ramus extends medially, and is connected with the lateral aspect of 



Fig.81: Intermuscular bones 

 of Phoxinus tennesseensis 

 CUT 44.5274. 50.0 mm SL) 

 (from caudal peduncle). Scale 

 bar = 1 mm. 



