4 PACIFIC COAST AVIFAUNA [No. 2. 



Study the effects of slope exposure, of prevalent fog currents, of soil, and of 

 relative dryness and humidity, for these are all to be observed within a 

 comparatively small area. It would be beyond the purpose of this outline 

 to enter into these problems. 



As stated above, the Humid Transition is a region of luxuriant vege- 

 tation though the number of species of plants is not large. Within the 

 Santa Cruz Mountains there is one of the finest small bodies of redwood 

 {Sequoia sempervircns) now extant. This forest is in the Big Basin, a 

 region drained l)y numerous creeks. From this center the forest, else- 

 where more or less broken, extends through many can>ons and frequently 

 up some distance on the ridges, where sooner or later it is replaced by the 

 Douglas spruce {PseiidofsuQa mucronata). 



The redwoods are thus typically found in the canyons. In this 

 dark still forest bird life is scarce. The boreal nature of the.se tracts is ex- 

 hibited by the presence of such plants as Achlys triphylla, Ahms oregana, 

 Azalea ocddciitalis, Cory/us rostrata califorin'ca, Goultheria shallon, Myrica 

 californica, Oxalis orcffaua. Rhododendron californicnm, Rubiis parviflorus, 

 Vaccinium parvifolimn, \ 'acriniiini oratnni, and WHiipplca niodesta. The 

 tan-bark oak {Qncrciis den.\i//ora ) is also found in this forest, but thrives 

 better upon the drier ridges with the Douglas spruce. Those forms char- 

 acteristic of the drier ridges, yet undoubtedly Transition, are the Douglas 

 spruce, tan-bark oak, madrone (Arhu/ns n/e/zz/es/ ), narrow-cone pine ( Piniis 

 atteniiata), mi{\v/.^x\\ii\i^ (Aretostap/ylfs i/iiinniii/aiia, A. andersoni ffa/ia), 

 mountain lilac (Ceaind/ii/s t/iyrsifiorns), mountain mahogany (Cercoiarpus 

 bctii/(rfo/ius), and on debatable land Oiincns wislizrni and Castanopsis c/iry- 

 sop/iy//a. Mention should also l)e made of the (lOwen cypress iCi/pressi/s 

 ooirniana) which is found on Ben L()mond and in other localities. 



Among those forms characteristic of the Upper Sonoran zone may be 

 mentioned the buckeye (.7iscn/iis ca/ifornica), liigeon-berry or wild cf ffee 

 { R/ianniiis ia/ifo))i/ca), chamiso ( Ado/ostonia fascinilaliivi), sage ( .ir/oi/isia 

 californica), and blue oak i Oiierciis dong/asi). 



The Santa Cruz Mountain region appears to be the home of a num- 

 ber of characteristic birds which, however, range to the southward, and 

 perhaps somewhat the northward. These are Jiouo /ivcinalis pinosns, 

 C/ianura faselata i>iterniedia, Pants riifescens barloici. Typical Thryoniancs 

 bcivicki spilioHs is found here and in the valleys around, and such birds as 

 Cyanocitta stcUcri carbonacea, Zonotrichia leiicophrys iinttalli, Anorfhnra 

 hiemalis pacijica, Sitta pygmcea and Dryobates villosiis harrisi, though of 

 wider distribution give a distinct tone to the region. 



W'ai^tfr K. Fisher. 



