1016 The American Naturalist. 
URODELA: 
Amblystoma 
Green. 
tigrinum 
SALIENTIA : 
Bufo cognatus Say.* 
Spea hammondii bombifrons 
Cope.* 
SERPENTES : 
Heterodon nasicus nasicus 
B. & G.* 
Ophibolus multistratus 
Kenn. 
Zamenis constrictor L.t 
Eutænia radix B. & G 
[December, 
Eutænia sirtalis parietalis 
ay. 
Eutænia elegans vagrans B: 
G 
Orotalus confluentus confluen- 
tus Say. 
SAURIA : 
Crotaphytus collaris Say. 
Holbrookia maculata B. & 
G; 
Phrynosoma douglassii her- 
nandesii Gir. 
Eumeces septentrionalis Bd.* 
Eumeces multivirgatus Hal- 
ow. 
Eumeces obsoletus B. & G. 
The species not marked with dagger or star are Chihuahuan, 
except Hutznia elegans vagrans, which is also found in the Basin 
district, E. sirtalis parietalis, which extends to the Pacific dis- 
trict, and the Amblystoma tigrinum, which is Medicolumbian 
throughout. 
The total number of species of the Sonoran subregion is as 
follows : 
Peculiar to the Chihuahuan district, 
Common to Lower Californian and Chihashean distic 
Peculiar to the Lower Californian district, . 
Peculiar to the Basin district, 
Common to the Basin and Chihtrafman; ; 
Peculiar to the Central district, ; ‘ 
Common to the Central and Chihuahuan, 
Common to the Chihuahuan and Texan, . 
Doubles emplois, . ¿ F i ‘ ee Pe 
