508 A. Smith Woodward — Affinities of Cydohatis. 



VI. — Note on the Affinities of the so-called "Torpedo" 

 (CrcLOBATis, Egerton) from the Cretaceous of Mount 

 Lebanon.' 



By A. Smith Woodward, F.G.S., F.Z.S., 

 of the Britisli Museum (Natural History). 



IN a paper read before the Geological Society in 1844,'^ Sir Philip 

 Egerton made known an interesting fossil Selachian from the 

 Cretaceous beds of Mount Lebanon, which he named Cydohatis 

 oJigodactylus, and referred to the TorpedinidjB, in consequence of its 

 apparently unarmed skin and the resemblance between its general 

 form and that of the familiar electric Torpedo. Six years afterwards 

 Pictet^ figured and described a second specimen of the fish, adding 

 some further particulars of the skeleton, and adopting Bgerton's 

 determination of its affinities. And quite lately,* Mr. James W. 

 Davis has made another contribution to our knowledge of the genus, 

 by describing a larger and more robust species under the name of 

 C major. The fish is again relegated to the Torpedinid^, and, so 

 far as I have been able to discover, the same original determination 

 has been universally adopted up to the present time. 



The fine series of specimens now in the British Museum, however, 

 appear to afford conclusive proof that the imperfections in Sir 

 Philip Egerton's original fossil led to an erroneous interpretation. 

 I have recently determined that the skin was far from unarmed ; 

 and a comparative study of the fins has shown that they are totally 

 distinct in character from those of all known genera of Torpedos, 

 while they approximate in a striking manner to those of the " Sting- 

 rays " or Trygonidse. There seems, indeed, to be no doubt whatever 

 that Cydohatis is truly a member of the last-named family ; and 

 there are four principal reasons why this position should be assigned 

 to it rather than that to which it has hitherto been referred. These 

 reasons may be concisely stated as follows. 



1. The pectoral fins are miinterru-ptedly continued to the end of the 

 snout, and were thus prohahly confluent in front. This, as is well 

 known, is one of the main characters of the Trygonidse, but it is a 

 condition apparently never met with among the Torpedinidee. I 

 have examined species of all the genera of the latter family, except 

 iJiscopyge, and find that, in no case, do the cartilages of the pectoral 

 fin extend in advance of the antorbital. 



2. The pelvic arch is placpA far forwards, and the rays of the pelvic 

 fins scarcely extend posteriorly beyond the extremity of the pectorals. 

 Though perhaps not of such fundamental importance as No. 1, this 

 peculiarity is much more suggestive of the Trygonidse than the 

 Torpedinidae, the living examples of the former often exhibiting it, 

 but the latter rarely or never. 



^ Eead before Section C, British Association, Manchester, 1887. 



^ Sir P. Egerton, " Description of a Fossil Bay from Mount Lebanon [Cyclolatis 

 oUgodactylus),'''' Proc. Geol. Soc. vol. iv. pp. 442-446, pi. 5. 



^ F. J. Pictet, " Poissons fossiles du Mont Liban," 1850, p. 55, pi. x. fig. 4. 



* J. W. Davis, « The Fossil Fishes of the Chalk of Mount Lebanon, Syria," 

 Trans. Royal Dublin Soc. [2], vol. iii. (1887), p. 491, pi. xxi. fig. 1. 



