iS86. 



Scott on the Birds of Arizona. 2 In ^J 



tory than in the Rillita, and it rises permanently to the surface 

 only at isolated points, in the form of springs or water holes. 



Having described with so much detail the region of the San 

 Pedro slope of the Santa Catalina Mountains in former papers 

 (see Auk, Vol. II, 18S5, pp. i and 243) it seems hardly neces- 

 sary to do more here than direct attention to them. To recapitvilate 

 briefly, the mountain range is here very wide, the foothills 

 extending far down — for at least eight miles — from the sum- 

 mit of the miin range. These hills, though generally abrupt 

 on the sides, are flat on top, thus forming mesas or tablelands of 

 greater or less extent, one ranging above the other. The canons 

 between these hills are narrow and deep, and in rainy seasons 

 there is a more or less continuous flow of water through them. 

 The canon in which mv house is situated has been alluded to be- 

 fore as having for a considerable distance an ever flowing stream 

 of water. 



To return to the consideration of the area as a whole, there are 

 two well defined rainy seasons. One, beginning early in Decem- 

 ber and lasting till about the middle of March, is a period of 

 storms rather than a rainy season proper. These storms consist 

 of rain or snow, according to the altitude, but snow is of so rare 

 occurrence on the plain of Tucson, that I can find but one record 

 of a snow storm having reached that locality during the past ten 

 vears. This season properly corresponds to the winter of the 

 East. It is succeeded l)v a period of spring, when the deciduous 

 trees regain their foliage, the plains become green and brilliant 

 with wild flowers. In June, most of these grasses and flowers 

 have ripened and died, and the plain is again brown and 

 withered ; and save for the scorcliing heat and the green leaves 

 of the trees, the countr\' has the appearance of \vinter. This sea- 

 son lasts for from six weeks to two months. 



The second rainv season begins generally rather late in July. 

 The rains are then of almost daily occurrence, beginning soon 

 after mid-day and clearing during the night ; are almost always 

 accompanied by thunder and lightning, and continue for from 

 three to six weeks. Coincident with this season of rain is a 

 second spring time, when the grass becomes much more luxu- 

 riant in its growth than in March and April, and the flowers 

 quite as abundant, but of more enduring varieties. Some of the 

 larger plants, too, as the ocotilla, having lost their first leaves 



