4 University of Michigan 



atripinnis at hand (for example, the topotypes of X. caliente). 

 In other lots, however, for instance that from San Miguel, the 

 dorsal may occupy either position, or an intermediate one. 

 Provisionally these differences are interpreted as of only 

 racial, not subspecific, value. 



As noted by Dr. Meek (1902), the young are blotched, in 

 coloration resembling Zoogoneticus rohustus and the young of 

 Characodon variatus, species of other genera (but of the same 

 family). These brown blotches are usually retained more or 

 less distinctly by the female, but soon become obsolete in the 

 male, which is the more deeply colored. In the adult the 

 color pattern, exclusive of the brown blotches on the female, 

 consists of dark marks, one on each scale. Each of these is 

 usually wedge-shaped, but not infrequently becomes narrowed 

 dorsoventrally and bordered with a very fine lighter streak. 

 In other specimens the dark pigment is mostly concentrated 

 toward the base and upper and lower angles of the scales, 

 leaving the center whitish, as in G. luitpoldi. The vertical 

 fins are often black in either sex. 



3. Goodea captiva Hubbs, new species 



Goodea atripinnis Meek, Publ. Field Mus., ZooL, 7, 1907, p. 156 (in 

 part: specimens from Jesus Maria only). 



This species is closely related to Goodea atripinnis, from 

 which it has doubtless been derived by isolation following 

 stream capture. The type-specimens come from one of those 

 tributaries of the Rio Panuco which are known to have ex- 

 tended their course backward until they have drained what 

 was formerly a part of the Lerma System. Another set of 

 specimens from the Panuco Basin, namely that from San Juan 

 del Rio, remains typical of G. atripinnis. Goodea toweri, also 

 from the tributaries of the Rio Panuco, is a very different 

 species. 



Goodea captiva differs from G. atripinnis in the form of the 

 body, the contours being more arched, the caudal peduncle 

 more slender; in the more anterior position of the dorsal fin, 

 the origin of which is equidistant from end of caudal and a 



