66 The Wilson Bulletin — No. 9!) 



(litions ideal beyond our most sanguine hopes. In fact, judg- 

 ing from the resuUs obtained in the vicinity, we concluded it 

 to he the most important, from an ornithological viewpoint, 

 of any for many miles in every direction, due solely to the 

 presence of permanent water with the accompanying lux- 

 urient desert vegetation. 



The portion of Rock Creek upon which we were located, 

 had its source (at this season) but a scant hundred yards 

 above our camp, disappearing into the thirsty sands about the 

 same distance below ; at both places forming large water- 

 holes supporting small clumps of medium-sized cottonwoods, 

 which, during all daylight hours, were literally alive with a 

 great variety of birds. It was in the vicinity of these two 

 sources of water supply with the intervening territory, that 

 ihe great bulk of our observations were made, the extraor- 

 dinary abundance of bird-life between and at these points 

 rendering their pursuit useless in the less likely desert re- 

 gions ; though, uf course, the latter were carefully studied as 

 well. 



In the neighborhood of the water-holes the creek banks 

 rose abruptly ; on the west with an almost impenetrable thicket 

 of thorn-bush and mesquite fringing a rugged plain, where 

 the higher growths of deciduous plants fell rapidly away to 

 barren flats of creosote-bush (Coz'illea), cholla (Opuiitia 

 cholla), and tree cactus (0. zjersicolor), with the beautiful 

 giant cactus or ''Sahuaro" (Cereiis gigaiitcus), either as sol- 

 itary trunks or gracefully branched like some giant candela- 

 bra. This plain stretched clear for twenty-five or thirty miles. 

 broken only by a few rolling hills and the narrow thread of 

 cottonwoods that marked the course of the (now dry) Santa 

 Rita River. 



To the east the bank rose sharply to a high stony ridge, 

 rough, hot, and cheerless ; covered with masses of the multi- 

 spined cholla, straggling growths of palo verde (Parkin- 

 sonia) and the ever-present sahuaros. Still on to the east 

 and north rose the beautifully modeled Santa Catalina Moun- 

 tains, bearing near their summits, heavy growths of cedar 



