NATURAL SCIENCES OF PHILADELPHIA. 



33T 



ON TWO NEW SPECIES OF SATIRODONTID^. 



BY E. D. COPE, A.M. 

 PORTHEUS LESTRIO, Cope. 



Represented by a portion of the cnminm, including both man- 

 dibnlar rami, and the maxillar}' and premaxillary bones of one 

 side, all with dentition nearly complete. The size of these parts 

 considerably exceeds that of corresponding ones in the tAvo other 

 species of the genus, and indicates a large and powerful fish. It 

 differs from the P. molossus and P. thaumas,^ in having three pre- 

 maxillary teeth instead of two, and in the relative positions, num- 

 bers, and sizes of the other teeth ; also in the prominent edentulous 

 superior distal extremity of the dentary bone. 



The first premaxillary is very large, the two others of moderate 

 size. These are followed by a long rugose diastema before the 

 maxillary teeth begin; these are, one small, five large, twenty-two 

 small, and eleven or twelve very small. The mandibular teeth 

 are, one very large, one immense, one small, one medium, four 

 small, eight large, and two small ; total eighteen. The teeth are 

 all simply round or oval in section, and the external, probabl}'' 

 cementum layer, is smooth. The maxillary bone has two large 

 superior proximal cond3des, separated by a space ; the anterior is 

 the narrower, and is directly behind the premaxillary condyle. 

 The anterior margin of the latter bone is very rugose. 



M. 



Length of tooth line of upper jaw 300 



" " premaxillary 058 



Depth, premaxillary (axial) . 

 " maxillary at second condyle 

 " " twentieth tooth 



Diameter base first premaxillary tooth . 



" bases five large maxillaries 

 Length of dentary above . ... 



Depth at second large tooth . 



" at last tooth 



Diameter base first large tooth 

 " " second " 



Length crown of second large tooth 

 " " sixth from behind 



.095 

 .095 

 .065 

 .018 

 .053 

 .270 

 .095 

 .105 

 .013 

 .020 

 .050 

 .025 



' See Proceedings Am. Philosophical Society (On Fishes of the Kansas 

 Cretaceous) January, 1872. 



