1917] Grinnell-Camp: Amphibians and Reptiles of California 129 
geographic nature. Here, where the data permit, series of record 
stations are given so as to outline roughly the range with regard to 
political boundaries and towns, or to features of the topography and 
drainage. Extreme points of occurrence on the north, east, south, 
and west are thus given, sometimes several in each direction where a 
long line is to be covered. For each of these the source of the record 
is mentioned. This may be in published literature, in some one’s 
unpublished notes, or from specimens in this museum. 
Secondly, where practicable, the lfe-zone in which the species 
occurs is given, for the purpose of bringing this paper into concordance 
with others on the distribution of California vertebrates. Thirdly, 
the habitat or associational restriction of the species is given. For 
an explanation of these two latter modes of distributional designation 
the reader is referred to a paper by the senior author (Grinnell, A 
Distributional List of the Birds of California’). 
The maps offered herewith serve to show the ranges of many of 
the species of amphibians and reptiles in California from a purely 
geographic standpoint. Stations of known occurrence are indicated 
by appropriate signs, and with some of the species we have ventured 
to indicate the outlines of the inferred ranges. By comparison of 
these maps one with another and with maps showing the distribution 
of birds and mammals in this state, a number of remarkable coinei- 
dences in distribution will be observed. It must be that similar or, 
possibly, the same factors operate to limit the distribution of such 
widely different kinds of animals. Much yet needs to be realized in 
the improvement of means of expressing the facts of animal distri- 
bution; only a mere beginning has been made in systematizing such 
knowledge as is already at hand. The meaning of distributional 
limitation is one of the most fascinating subjects claiming the attention 
of the field biologist. Really satisfactory inquiry into the underlying 
causes must await the accumulation and assortment of vastly more 
data than are here presented for reptiles and amphibians, and the same 
degree of exhaustiveness must be applied to many different areas. 
Most of the heretofore unpublished data used in the present paper 
have been gathered during the past eight years for the Museum of 
Vertebrate Zoology by various field parties working in its employ. 
For the expense of bringing together and caring for the collections of 
reptiles and amphibians now accessible in this museum, workers in 
herpetology are indebted to Miss Annie M. Alexander. For the 
3 Pacific Coast Avifauna, 11, 1915, 217 pp., 3 pls. 
