MONTHLY RAINFALLS 39 
“The Pacific Type. — This type is found in all 
of the territory west of the Cascade and Sierra Nevada 
ranges, and also obtains in a fringe of country to the 
eastward of the mountain summits. The distinguish- 
ing characteristic of the Pacific type is a wet season, 
extending from October to March, and a practically 
rainless summer, except in northern California and 
parts of Oregon and Washington. About half of 
the yearly precipitation comes in the months of 
December, January, and February, the remaining 
half being distributed throughout the seven months 
— September, Uciaber November, Moreh, April, 
May, and June.” 
“ Sub-Pacific Type. — The term ‘Shub-Pacific” has 
been given to that type of rainfall which obtains over 
eastern Washington, Nevada, and Utah. The in- 
fluences that control the precipitation of this 
region are much similar to those that prevail west. 
of the Sierra Nevada and Cascade ranges. There 
is not, however, as in the eastern type, a steady 
diminution in the precipitation with the approach 
of spring, but rather a culmination in the precipi- 
tation.” 
“Arizona Type.— The Arizona Type, so called 
because it is more fully developed in that territory 
than elsewhere, prevails over Arizona, New Mexico, 
and a small portion of eastern Utah and Nevada. 
This type differs from all others in the fact that 
about 35 per cent of the rain falls in July and 
