THE BATEACHlA OF NORTH AMERICA. l87 



tail is that of ^. luguhris, and not tliat of A. iecanus. Bat one speci- 

 men has come under my observation, as follows: 

 No. 6794; 1 specimen ; Fort Umpqua, Oregon ; Dr. Yollen. 



AUTODAX liiCANUS Cope. 



PJelJiodon iecanus Cope, Proceed. Ac. Phila. 1883, p. 24. 



Anaides iecanus Cope, Proceed. Amer. Philosoph. Soc, 1888, p. 526. 



A fully grown individual of this species presents the following char- 

 acters: The form is rather robust, and the head is dislinguished from 

 tlie necli by the swollen temporal muscles. The muzzle is short and 

 wide, with rounded border, and is not so contracted as in the A. liuja- 

 brlfi. The length from the end of the muzzle to the axilla enters that 

 from the latter to the groin one and a half times. The tail is of moderate 

 length, equaling that of the body (including vent) nearly to the thoracic 

 fohl. The width of the head enters the length from end of muzzle to 

 groin five and one-half times— a proportion intermediate between those 

 exhibited by the two other species of the genus. The limbs are rather 

 robust, and when appressed to the sides leave an interval of three 

 intercostal spaces. 



The top of the head is flat, and the least interorbital width is equal 

 to the length from the eye to the end of the muzzle and to the space 

 inclosed between the external borders of the external nares. The 

 commissure of the mouth rises behind the line of the orbit as in the J.. 

 liiguhrU. The muzzle does not project beyond the mouth, as it does in 

 A. luguhris. The internal nares-are very small. The tongue is large 

 and anteroposteriorly oval, and is extensively free at the sides. The 

 vomero palatine teeth are in two short rows of three or four teeth each, 

 which commence behind the internal nares, on a line with their inter- 

 nal. borders, and converge, with slight posterior inclination, without 

 meeting. The patch of parasphenoid teeth is wide and subtruncatein 

 front, and is undivided except towards the posterior portion. The 

 large teeth of the jaws are not so well developed as in the A. luguhris^ 

 are more slender in form, and not so numerous. They constitute the 

 entire armature of the dentary bone, occupying only the anterior half. 

 1 count only four of them, and they are movable; that is, immature. 

 I find no fixed ones of the larger size in the u])per jaw. Three or four 

 of the posterior maxillary teeth are like those of the dentary bone, but 

 they graduate anteriorly into teeth of the usual type. An examina- 

 tion of other specimens will benecessary to ascertain whether these teeth 

 become permanent or not, or whether they are developments of the 

 breeding season. The large temporal muscles, curved commissure of 

 the mouth, etc., so resemble the corresponding parts in the A. luguhris, 

 that I suppose their permanent dental characters to be alike. The max- 

 illary bone projects abruptly downwards behind the last maxillary 

 tooth, forming a smooth edge, as in A. luguhris. 



