13. COLUBRIDAE 



of the frontal plate, crosses the supraocular and parietal 

 plates, passes out over the temporal region, and becomes 

 narrower and parallel with its fellow upon the neck. On the 

 parietal plates is a brown spot, elongated posteriorly. The 

 dorsal region is occupied by a series of dark brown, paired 

 blotches, of which there are from 21 to 28 between the head 

 and anus. There is an irregular series of dark lateral spots, 

 alternating, and so.Tietimes confluent, with the dorsal 

 blotches. Anteriorly these lateral spots may form a narrow 

 interrupted band. There are nine or 10 confluent pairs of 

 dark spots on the upper surface of the tail. The entire 

 lower surface is whitish, except that a series of spots involves 

 the tips of certain of the gastrosteges, the spotted scutes be- 

 ing separated by from two to five unmarked ones. 



Length to anus 588 588 600 835 



Length of tail .110 108 110 155 



Distribution. — This species of Trimorphodon has been 

 found only in southern Arizona and in Lower California. 

 In Arizona, it has been secured in the Cayetano Mountains 

 near Calabasas and at Fort Buchanan, Santa Cruz County, 

 at Fort Huachuca, Cochise County, and in the Tucson Range 

 and near Rosemont, Pima County. Lower Californian 

 specimens have been collected at Cape San Lucas, La Paz, 

 San Jose del Cabo, Sierra San Lazaro, Santa Anita, and 

 Santa 



Remarks. — Professor Cope described the teeth as fol- 

 lows: 



Seven teeth upon the superior maxillary bone, of which 

 one posterior is elongate and grooved, three central, small 

 and recurved, and three anterior, very long, the first longest 

 and least recurved. The central three are not separated 

 from those anterior and posterior to them by spaces wider 



