from the English Lower Lias. 435 



specific name. From this the fish now made known is dis- 

 tinguished by the more remote situation and relatively smaller 

 size of the dorsal fin, and probably by less conspicuous cha- 

 racters at present imperfectly revealed. The name of Cocco- 

 lepis h'assicus is thus proposed for the new species, in refer- 

 ence to its stratigraphical position. 



II. Family Ccelacanthidae. 

 Genus Undina. 



Well-preserved examples of a large Coelacanth Ganoid 

 (Holophagus gulo) have already been described by Egerton 

 and Huxley from the Lower Lias of Lyme Regis ; but no 

 member of the same family has hitherto been detected in a 

 corresponding horizon elsewhere. The British Museum, 

 however, now furnishes evidence of a distinct species from 

 the Lower Lias of Barrow-on-Soar, Leicestershire ; and, 

 although the specimen is not so satisfactorily preserved as 

 desirable, it exhibits several features specially worthy of note 

 in comparison with the Coelacanths both of earlier and later 

 date. The fossil occurs on counterpart slabs, and one is 

 shown, of the natural size, in PL XVI. fig. 5. 



The head and the greater portion of the trunk are exhibited 

 from the lateral aspect, the anal and paired fins only being 

 entirely wanting. The head and opercular bones, so far as 

 preserved, do not exhibit any external ornamentation, though 

 some rounded pittings in an impression of the operculum 

 may possibly indicate the presence of a few large rounded 

 tubercles upon that bone. Above the orbit a series of small 

 quadrangular plates (x) may be either parafrontals or scle- 

 rotics ; and one of the pterygo-quadrate elements (ptq.) is 

 seen, with obscure traces of small conical teeth. The im- 

 pression of the inner aspect of one of the jugular plates (ju.) 

 is also distinct, proving that bone to have been narrow and 

 elongated, nearly four times as long as its maximum width. 

 The first dorsal fin (d 1 ) exhibits not less than seven very 

 long stout rays, articulated in the distal half, and the anterior 

 margin of the first ray is fringed by well-developed upwardly- 

 pointing denticles*. The second dorsal (d 2 ), though much 

 broken, is evidently smaller than the first and consists of very 

 slender rays. The hinder half of the caudal region is dis- 

 placed, almost severed from the rest of the fish, and partly 

 destroyed. Sixteen rays can be distinctly counted in the 



* These denticles are scarcely seen cm the slah figured, but are distinct 

 on the counterpart. 



31* 



