THE GYMNOTID EELS OF TROPICAL AMERICA. 



183 



size showed the part removed to have been about sixty-five millimeters long and 

 ten by six millimeters deep at its base. In repairing these injuries neither had 

 regenerated a caudal peduncle. Instead, from the line of injury both had regen- 

 erated a broad fan-shaped fin, nine millimeters long on fish "A" (Fig. 23) and 



Fig. 23. Regenerated Tail of Sternarchorhamphiis mulleri (Steindachner) . Fish "A." 



twelve millimeters on fish "B" (Fig. 24). Both regenerated fins had the shape of 



Fig. 24. Regenerated Tail of Sternarchorhamphus mulleri (Steindachner). Fish "B." 



the normal caudal fin, from which they differed in three particulars, (1) both were 

 much larger than the normal caudal; (2) each contained more rays than the 

 normal caudal which has only ten raj^s, while the regenerated fin of specimen "A, " 

 nine millimeters long, contained twenty, and the fin of "B, " twelve millimeters long, 

 contained twenty-six rays; (3) they were situated at least fifty millimeters nearer 

 the head than the normal fin, arising from the body directly and not from the 

 sUm caudal peduncle. The fin twelve millimeters long differed in still another 

 respect; it was confluent ventrally with the anal fin. Figures 23 and 24 show the 

 regenerated fins "A" and "B" respectively, and Figure 25 a normal caudal of this 



Fig. 25. Normal Tail and One Fourth of Caudal Peduncle. Sternarchorhamphus mulleri (Steindachner). 



species. The third specimen had lost only the caudal fin and the extreme tip of 

 the caudal peduncle. From the old tissue a small bud of new tissue projected. As 

 this was quite small and showed no structure, it is probable that this fish had been 

 injured only a short time before it was captured. 



No specimens of SternarcJms albifrons Linnaeus, Sternarchus leptorhyncMis 

 Ellis, or Porotergus ginibeli Ellis, were found with regenerations, and, the last 

 named two species being new, no mutilations have been noticed by others. On 



