512 On the CretaceoH.H Fish Protospliyraena. 



very closely pressed together ; in both cases the anterior edge 

 of the fin is oblique, some of the anterior rays terminating 

 successively at tiie border (considerably more in Proto- 

 sjihijrcpna than in Hypsocormus) ; and in both cases the 

 anterior edge is roughened by a deposit of a hard enamel- 

 like substance. Unfortunately there is as yet no precise 

 information concerning the basal bones of the pectoral fin 

 in llyjysocormus. 



(7) Axial Skeleton of Trunk. — Negative evidence can only 

 be regarded as of slight value, but it is nevertheless note- 

 worthy tliat traces of veitebra? are wanting in all the known 

 specimens of Protosphyrcena. It seems likely indeed that this 

 fish will eventually prove to have possessed a persistent note- 

 chord as devoid of peripheral ossifications as that of Hypso- 

 cormus and Pachycormus ; and in this connexion it is of 

 interest to record that two fragmentary examples of the trunk 

 of a small Hypsocormus -Yike fish have been discovered in the 

 Upper Cretaceous of Sahel-el-Alma, Mount Lebanon. One 

 of these specimens is in the British Museum (no. 49531) and 

 the other in the Syrian Protestant College, Beyrout ; and 

 although no remains of a Protosphyrce)ia-\'ike skull have 

 hitherto been met with in the same deposit, the present writer 

 has little hesitation in predicting that such will eventually be 

 found. The axial skeleton of the trunk in these fossils 

 exactly resembles that of Hypsocormus in the form and 

 disposition of the close series of neural and hieraal arches ; 

 the squamation cannot be distinctly seen, but must have been 

 very delicate ; and the remains of the dorsal fin are well in 

 advance of those of the anal fin. 



In conclusion, it may therefore be stated that Protosphyrcvna 

 is not a " Teleostean " in the ordinary acceptation of the 

 term, and that none of its characters hitherto discovered 

 warrant its separation from the family to which the Jurassic 

 genera Hypsocormus and PacA^cor/^ws are referred. It differs 

 from both in the lateral compression of the teeth, and future 

 discoveries may reveal still more distinctive features ; while 

 it is not easy as yet to estimate the true value of some of the 

 points of resemblance noted above. It must suffice at 

 present merely to suggest a profitable form of comparison to 

 be made when still more satisfactory specimens of Proto- 

 sphyrctna arc available lor study. 



