578 peof. t. w. beid&e ok the mesial 



lophobeanchii. 



Stn&nathid^. 



Siphonostoma typhle. 



Here is a well - developed dorsal fin and a small, almost 

 vestigial anal fin. 



Dorsal fin. — This fin consists of thirty-four bisegmental radial 

 elements, supporting a like number of soft fin-rays. The 

 proximal radial segments are very slender splint-like bones 

 -without any trace of lateral longitudinal ridges, and exhibiting a 

 slight tendency to become arranged in groups of four each. In 

 each group the segments converge slightly towards their 

 proximal ends, where they are firmly attached to the summit of 

 the neural arch of a subjacent vertebra. Distally, the segments 

 diverge slightly and their dorsal extremities expanding some- 

 what come into apposition, and form with one another and with 

 those of other groups a continuous peripheral margin. The 

 distal segments consist of a series of rounded cartilaginous 

 nodules connected with one another longitudinally by ligament, 

 and but loosely connected by the same means with the distal 

 extremities of the proximal segments. 



The fin-rays are slightly bifurcate at their basal extremities 

 and partially embrace the distal radial segments, to which they 

 are intimately united by fibrous tissue. 



JBLippocampus guttulatus. 



Except for reduction in number, the fin-rays and their radial 

 elements in this species are essentially similar to those of the 

 preceding. 



Plectognathi. 



scleeodeemi. 



JBalistes capriscus. 



Anterior Dorsal fin . — The three spinose rays, with theirosseous 

 supports and muscles, in Balistes vetula have been described 

 and figured by Sorensen [10]. The corresponding structures in 

 B. capriscus are precisely similar, except for the diminutive 

 size of the third spine. The radial elements supporting the 



