440 PEOF. ST. GEOEGE MIVAET ON THE 



up of three cartilages fused together. After the first, they are of nearly equal length 

 till about the seventeenth, whence they rapidly diminish in length postaxiad. 



The median cartilages are slightly larger than the basal ones, and are twenty-nine in 

 number ; but one or two bifurcate distally. They are more equal in length than either 

 of the other series, and are longest at the preaxial end, i. e. at about the sixth radial. 



The distal cartilages are far the longest and most unequal (being shorter both pre- 

 and postaxially) and far longer medianly than any of the median or basal cartilages. They 

 are twenty-nine in number, the twelfth, thirteenth, and fourteenth being the longest. 

 Each reposes proximally on the distal end of a median cartilage, except the last but six, 

 which seems intercalated between the distal ends of the adjacent median cartilages. 



The Pectoeal Fin. 



The skeleton of this fin I found to closely resemble that of Carcharias glaucus, as 

 represented by Professor Gegenbaur ^ except that the metapterygium was more seg- 

 mented and the propterygium somewhat larger and more prolonged. 



The Ventral Fin. 



The order much resembled that of C. glaucus, as shown by the last-named author ^^ 

 save that there was no thick preaxial radial ; but I found that four slender ones joined the 

 . pelvic cartilage, while, instead of one stout radial ; three slender ones were appended to 

 the distal end of the basal supporting cartilage of the ventral fin. 



LAMNA CORNUBICA. 



Dorsal Fin (Plate LXXIV. fig. 2). 



The skeleton of this fin exhibits much general resemblance in outline to the 

 corresponding one of Zygcena malleus ; but the basal cartilages are very much elongated 

 at the expense of the median series, which are found only in the postaxial half of 

 the fin. 



The hasal cartilages are twenty-four in number, and, after the first two, attain at once 

 their greatest length, decreasing postaxiad after about the fifteenth. The five most 

 postaxial radials are segmented ; but they may have been fractured. 



The median cartilages are only twelve ; and all are very short, and interposed 

 between the more postaxial radials of the other two series. 



The distal cartilages are extremely elongated, and number twenty-three, the eleven 

 more preaxial of which repose directly on the distal ends of the basal cartilages, the 

 others resting on the short median ones. 



' XTntersuchungen, Heft ii. plate tx. fig. 5. 



^ " Die Gliedmassen der Wirbelthiere im Allgemeineu," in .Jenaische Zeitsohrift, vol. sv. plate xv. fig. 9. 



