NO. 2211. GENERA DESMOGNATHUS AND LEUROGNATHUS—DUNN. 405 



Zonal range transition. Vertical range: 500 feet (Clarke County, 

 Virginia), 4,500 feet (Tatula Mountain, North Carolina). 



1. D. fusca. 



2. D. auriculata. 



3. L. marmorata. 



Fio. 13.— Ranges of 1, Desmoqnathus fusca fusca; 2, D. fusca auriculata; 3, Leurognathus 



MARMORATA. (DOTTED AREA SHOWS INTERGRADATION.) 



Diagnosis. — Vomerine teeth not lost by males on reacliing sexual 

 maturity. (The largest and probably the oldest males lack these 

 teeth. Others, however, many as large as the largest /i<sca and un- 

 doubtedly sexually mature, have these teeth. When lost it is a 

 senile change.) Parasphenoids confluent anteriorly. Legs stout. 



