green: ENCHODUS in KANSAS MUSEUM. gS 



an error. He has figured the right palatine complete with its 

 fang, the cephalic end being placed to the right in the figure, 

 and describes it in the text as showing the mesial side. He 

 says, "The figure represents the inner side of the tooth, and 

 shows the inner, or posterior, cutting edge." Further on he 

 describes an outer cutting edge, and the cross section of the 

 fang (fig. 60a, 1. c.) shows that if one cutting edge is directed 

 outward there can not be an inner cutting edge. To make this 

 description intelligible it is necessary to substitute the word 

 "outer" for "inner" in the two places where the latter occurs 

 in the sentence quoted. 



This museum contains two pairs of entire palatines of this 

 species, and with the change suggested the description fits very 

 well. Doctor Hay is evidently in error concerning the palatine 

 and the bones that articulate with it caudally and dorsally in 

 this species. Several of the specimens of E. jjetrosus show the 

 pterygoid firmly attached to the palatine, caudally. There are 

 numei'ous other species in the collection which show this same 

 arrangement with regard to these two elements. 



There are also several specimens which display just such 

 a posterior aspect as is shown in Hay's figures 61 and 62 

 (1. c). In view of the fact that so many specimens indicate a 

 firm union of these bones, it would seem that these smooth 

 surfaces must be explained in some other way, perhaps by 

 weathering. The specimen described as an interopercular (fig. 

 65, iop, 1. c.) seems to have three rather prominent ridges and 

 other less marked ridges and grooves radiating from a point 

 near the anterior border, and a single row of teeth charac- 

 teristic of a premaxillary of E. petrosus. Since Doctor Hay 

 was in doubt concerning this element, and the author has be- 

 fore him a specimen of E. petrosus which has the premaxillary 

 present, so greatly resembling Doctor Hay's figure, he is in- 

 clined to think that the Specimen in question is not an oper- 

 cular, but a premaxillary. 



Figure 1, plate H, shows an opercular, parasphenoid, pala- 

 tine and caudal end of the skull of a specimen of E. petrosus. 

 It is No. 804. The opercular shows the mesial view, which is 

 smooth except for the rather stout bar extending caudad from 

 the articulation with the hyomandibular; pal, pal' and paid 

 represent a ventral, an external and a dorsal view, respec- 

 tively, of the left palatine, the most complete of any in the 

 entire collection. The mesial side of this bone sends caudad a 



