134 Mr. A. S. Woodward on some 



short, longitudinal rugae ; an anterior and a posterior keel 

 divide tlie external face from the internal, and the latter is 

 often faintly ribbed by numerous straight longitudinal ridges. 

 Some examples are figured by Allport {loc. cit.). 



Pisces. 



All the fish-remains collected by Mr. Mawson were ob- 

 tained from the same beds as the Crocodilian teeth upon the 

 coast, and the determinable specimens belong to the four 

 genera Diplomystus, CMromystus^ LepidotuSy and Acrodus. 



Diplomystus longicostatus^ Cope. 



A small fragment of this species does not add anything to 

 Professor Cope's description ; but it may be remarked that 

 the occurrence of the genus in the Bahia sandstones is not so 

 unexpected a circumstance as might be inferred from the 

 Professor's concluding paragraph. In the first place, the 

 deposit is clearly not marine, but freshwater or estuarine, as 

 demonstrated by the Mollusca and Entomostraca * ; and, in 

 the second place, at least one species of Diplomystus is abun- 

 dantly represented in the Upper Cretaceous beds of Syria. 

 Though not hitherto detected, the common ^^Clupea hrevis- 

 sima '"' of Mount Lebanon exhibits all the typical characters 

 of Diphviystus. The dorsal scutes are seen in almost every 

 example, and are especially well displayed in Brit. Mus. no. 

 49488 ; they are at least as broad as long, with a longitu- 

 dinal keel ; and the elongate anal fin is quite similar to that 

 of the Wyoming Eocene D. analts and D. pectorosus^ though 

 comprising a slightly less number of rays. 



Chiromystus 3Iaivsom\ Cope. 



The specimen upon which Prof. Cope founded the new 

 genus and species Chiromystus Mmosoni is a large elongated 

 fish, with the vertebral column measuring 0-310 m. in 

 length. It is placed in the Hyodontidye, and particularly 

 characterized by the enormous development of the preaxial 

 pectoral fin-rays. Of this genus also the present collection 

 comprises two interesting fragments, the one showing some 

 anterior vertebras and crushed bone, with the left clavicle and 

 pectoral fin, the other the greater portion of the abdominal 

 and caudal regions. The stout pectoral fin-rays are exhi- 



_ * See descriptions of JNIorris and Rupert Jones iu AUport's paper, loc. 

 cit. 



