1903.] Hay, North American Cretaceous Fishes. ']'] 



Length of the lower jaw from the chin to the articular con- 

 dyle 223 mm. 



Height of the jaw at the coronoid process 67 mm. 



Breadth of the skull at the postorbitals iii mm. 



Length of the palatine and prefrontal to the front of the fang 7 2 mm. 



Unfortunately the whole surface of the specimen has been 

 covered and in some places injured by a deposit of crystals 

 of gypsum, so that it is difficult to determine some structures. 

 Other structures and the general forms of the bones are dis- 

 tinct enough. The number of the specimen is 198. 



The distinguishing character of this species is found in the 

 great palatine fang. In other American species of the genus 

 where the palatine fang is known the latter is compressed 

 laterally. In the present species the compression is nearly 

 antero-posterior. The species is nearest to E. petrosus, with 

 which it was at first identified. 



The right palatine bone (Fig. 58) is in excellent condition, 

 barring the deposit of gypsum on its sur- 

 face. It has suffered little or no distortion tiM^m^sJ.-^ 

 or compression. No part of the ectoptery- 

 goid adheres to it. The figure represents 

 the inner side of the tooth and shows the 

 position of the inner, or posterior, cutting 

 edge. The greater part of the fang is pre- Fig. 58. Emhodus sa- 

 served. The left palatine is distorted and Type.""^' Right'^paiadne 

 has lost all but the base of the fang. bone and fang 



In E. petrosus a sharp cutting edge begins at the base of the 

 fang in front and runs downward to the tip (Fig. 59). This 

 is very distinct from the first, and it pursues its course near 

 the anterior midline of the tooth, separating an outer from an 

 inner face. The section shown in Fig. 59, h, ought to have been 

 taken somewhat higher up on the tooth, in which case the 

 inner face (on the left) would have been somewhat more con- 

 vex, but it would still have differed much from Fig. 60, a. In 

 E. sceviis (Fig. 60) there is a faint trace of a corresponding 

 edge and it may once have been stronger, but it lies much 

 nearer the inner side of the tooth. Another cutting edge 

 starts at the outer side of the base of the tooth; but, instead 



