20 University of California Publications in Zoology [Vol. 27 
region. Several genera ( Dicamptodon , Batrachoseps , and Ascaphus) 
are restricted to the western half, or less, of the continent. Aneides 
has until recently (Dunn, 1923a) been considered a strictly western 
genus, and I believe strong evidence is necessary to warrant its exten- 
sion to include an eastern form. 
The relationships of the west coast fauna have not been fully in- 
vestigated as yet. Stejneger (1905a, b) has suggested a center of 
origin for the discoglossid toads in southeastern Asia; Dunn (19235) 
states that the relationships of Triturus torosus are with an Asiatic 
species rather than with T. viridescens of eastern North America. 
Cope (1889) listed our Rana aurora as a subspecies of the Eurasian 
agilis and our Rana pretiosa as a subspecies of the Old World tempo- 
raria , a grouping not without merit. (See also Cope, 1896.) Among 
birds and mammals there are numerous forms which indicate close 
faunal affinities of the North Pacific and Northeast Asiatic coasts. 
On the other hand, the Californian fauna undoubtedly includes 
some southern (Sonoran) elements. Scaphiopus hammondii, several 
of our Bufos ( cognatus , punctatus, woodhousii) , and Hyla arenicolor 
are widely distributed in the American southwest and some of these 
have probably evolved in this region. 
The accompanying table indicates in a general wav the distribu- 
tion of the various species of amphibians in California as known at 
the present time. An attempt was made to define the ranges in terms 
of life-zones as these zones are currently mapped in California. Some 
species conform to these zones fairly well, yet there are numerous 
exceptions, and there are also serious gaps in our knowledge of the 
extent of range for a number of species, so that an exact mapping 
by life-zones seems impracticable at the present time. 
For example, Triturus torosus occupies in southern and central 
California the Upper Sonoran Zone (and even portions of the Lower 
Sonoran Zone) ; in the northwestern part of California it is present 
in the Upper Sonoran and Transition zones; near South Yolla Bolly 
Mountain it occurs in territory referable to the Canadian Zone ; in the 
Cascade Mountains of Oregon it has been reported in territory which 
is also Canadian ; and in southeastern Alaska its zonal status is Cana- 
dian. In the Sierra Nevada this salamander has not been found above 
the Upper Sonoran Zone save at Cisco, Placer County; its general 
exclusion from the Transition may be due in part to the zonal differ- 
ence in temperature, but I believe lack of suitable environmental con- 
ditions is a more potent factor in its absence there. 
