204 University of California Publications in Zoology [Vol. 10 



catelaw, screwbean, and arrowweed, with an occasional cotton- 

 wood along the creek. 



Farther up the canon, at our higher camps (2500 to 3000 

 feet), we were above the region of palm trees, and in the agave 

 belt. Great numbers of these plants were in full bloom in June 

 on the sunny sides of the surrounding ridges, especially east of 

 the stream, while the shaded slopes were grown up with a rather 

 scattered growth of yuccas, junipers, and scrub oaks. Along the 

 stream were willow, desert willow (Chilopsis) , and a few cotton- 

 woods. 



At the termination of our stay in Palm Canon, we traveled 

 directly to Dos Palmos, leaving Palm Canon at ' ' Little Paradise, ' ' 

 ascending a draw to Potrero Spring, skirting Asbestos Mountain 

 on the west and south, and then crossing the northern portion 

 of Pihon Flat. At the summit of the ridges the north sides are 

 scantily clothed with pifion and scrub oak, the south sides and 

 flats clown to 2500 feet with juniper, agave, a species of Pruwus, 

 catelaw. yucca, several species of cactus, and other desert plants. 



Garnet Queen Mine 



On the western slope of Santa Rosa Mountain, at 6000 feet 

 altitude. The mine is abandoned, and the old cabin pertaining 

 to it proved to be a convenient place at which to camp. This 

 was in a steep and rather narrow canon, at the extreme lower 

 edge of the Transition zone, which is here very sharply defined 

 against the Upper Sonoran just below, the change from grease- 

 wood-covered Upper Sonoran hills to pine-timbered Transition 

 being made within a distance of about one hundred feet. North 

 of camp was a chaparral-covered ridge, brushy down to within 

 a hundred yards of the caiion bottom, while the south slope 

 (north facing) was timbered to the top, the usual effects of such 

 slope exposure emphasized by the cutting off of the dry. hot 

 desert air-currents by the first mentioned ridge. Some Transition 

 zone plants at this point were the many incense cedars and 

 silver firs, a few yellow pines and sugar pines, many golden 

 oaks, willows, Amorpha, Bibes, and Symphoricqrpus. The region 

 was prolific in bird and mammal life, as well as in insects. In 



