FINS OF GAT!fOIDS AND TELEOSTS. 573 



has a " chain-link " articulation witli the first ray, and, besides 

 furnishing a hook-like process which curves backwards and 

 hooks into the perforated base of the second ray, contributes by 

 its distal segment to the support of its proper ray — the third. 

 The remaining fin-rays clip their distal radial seo:ment3 in the 

 usual fashion, but the last two are both supported by the 

 same distal segment, viz., that belonging to the last radial 

 element. 



BLENNIIDiE. 



Anarrliichas lupus. 



Dorsal fin. — In the long dorsal fin of this species there are 

 seventy-five radial elements and seventy-six long flexible spinose 

 fin-rays. All the radial elements are unisegmental (PL XXIII. 

 fig. 31), consisting only of proximal segments {p.s.) without any 

 trace of mesial or distal segments ; and, with the exception of the 

 last, all support in a precisely similar fashion their respective fin- 

 rays. Near its distal extremity each proximal segment abruptly 

 contracts into a nearly vertical postero-superior process, and from 

 the anterior surface of this process a slightly curved bony hook 

 extends forwards. The anterior extremity of the hook is con- 

 nected by ligament with the distal end of the postero-superior 

 process of the proximal segment immediately anterior, and I have 

 no doubt that in this species, as with the second radial element 

 of the anterior dorsal fin oiMugil, the hook owes its existence to 

 the partial ossification of the ligament (interossicular ligament) 

 which extends between the postero-superior processes of con- 

 tiguous proximal segments. On the anterior side of the base of 

 the postero-superior process there are two laterally situated 

 facets (/c.) for the fin-ray. 



Each fin-ray {f.r.) is cleft proximally into two basal arms, 

 which converge somewhat without actually meeting, and finally 

 terminate in two condylar extremities. Each ray is supported 

 solely by a single radial element, partly by its two basal condvles 

 which articulate with the two facets at the base of a postero- 

 superior process, and partly by the extension of the hooked 

 process of the latter through the nearly complete foramen 

 enclosed by the cleft base of the ray. The rays are further 

 retained in position by a stout longitudinally disposed lio-ament 

 passing between their basal extremities, and also between the 

 postero-superior processes of successive proximal segments. Of 



