566 PEOF. T. W. BBIDGE Olf THE MESIAL 



of tte proximal segment by " chain-link " articiilations (r.e.^,p.s.}. 

 Three vestigial proximal segments without fin-rays lie anterior 

 to the first ray-bearing radial element. 



In the soft posterior section of the fin there are fourteen 

 radial elements, exclusive of a small vestigial proximal segment 

 behind the last ray-bearing element. All are bisegraental 

 (fig. 25) except the last four, which, curiously enough, possess 

 a separable mesial segment, and are therefore trisegmental, and 

 each supports a soft fin-ray. The connexion of the rays with 

 the distal segment is by means of a " peg-and-socket " articulation 

 in the case of the more anterior ones ; posteriorly, however, the 

 cleft rays merely embrace the distal segments. 



Anal fin. — In this fin there are nine radial elements, of which 

 the first to the sixth inclusive are bisegmental (PI. XXII. fig. 26, 

 r.e}-r.e?^ and the last three trisegmental. The first supports 

 three spines, two by means of " chain-link " articulations and 

 the third by its hooked distal segment, precisely as in the first 

 radial element of the dorsal fin. The remaining eight soft rays 

 are also supported in much the same way as those of the hinder 

 section of the dorsal fin. 



There is a small vestigial proximal segment immediately 

 behind the last ray-bearing element. 



Spaeid^. 

 Fagellus centrodontus. 



Dorsal fin. — In Pagellus the dorsal fin consists of twenty 

 radial elements, of which the anterior ten support twelve spinose 

 rays and the remainder a series of soft rays. Anterior to the 

 first spine-bearing element three vestigial elements are represented 

 by their massive T-shaped proximal segments without fin-rays. 

 The spine-bearing elements are almost precisely similar to those of 

 Perca. The postero-superior processes of the proximal segments 

 and the distal segments possess unusually well-developed lateral 

 wings, so that the groove for the deflected spines is exceptionally 

 well marked. 



In addition to its proper ray, the third, the first radial element 

 supports two additional spines, of which the first has an incom- 

 plete " chain-link " articulation with the distal end of the proximal 

 segment and the second a complete one. 



The ten radial elements which support the soft rays are all 

 bisegmental, resembling in this respect, as well as in the method by 



