906 U.S. NATIONAL MUSEUM BULLETIN 23 7 part 2 



or greater from July 11 to December 25, 1951, except in the period 

 August 29 to October 24; but only 7 millimeters (0.27 inch) fell from 

 Dec. 26, 1951, through Feb. 29, 1952, which is normally the winter 

 rainy season. 



Naturally, this abnormal weather produced an unusual reaction in 

 the habitat. Most obvious, though probably not important to our 

 sparrow, was a veritable plague of greasy cutworm moths and other 

 adult Noctuidae at the end of March and later. Robert H. Crandall 

 {in litt.) noted several other unusual features near Tucson; the 

 usually dry- and dead-looking "burro-brush," (Hymenoclea pentalepis 

 and perhaps also H. salsola and H. monogyra), a thin wiry next-to- 

 nothing, was green and succulent about the first of April; evidently 

 it was well supplied with minute inchworms (Microlepidoptera), whose 

 pupae he found about April 20. In late April he saw some big 

 caterpillars of a sphinx moth which usually appear only after the 

 summer rains start; and from early to mid-May (approximately) 

 many inchworms appeared on the native palo verde trees. 



The rainfall pattern of 1957-58 was generally similar to that of 

 1951-52. After Sept. 1, 1957, no rain fell until October, which was 

 very wet. Light rains continued to December 7, but from December 

 16 through February 3 no measurable rain fell. Then a succession 

 of storms wet the valley from February 4 thi-ough April 9, with later 

 sprinkles on April 16 and May 11. The summer rains began on 

 June 20 and 26. 



I have little information on the ecological picture of 1957-58, 

 for Robert Crandall had moved away. A plague of big gi-asshoppers, 

 Trimerofropis pallidipennis, occurred in and near Tucson from May 5 

 to about May 10 (and later?) ; at the same season Floyd G. Werner 

 noted a plague of false chinch-bugs, Nysius raphanus. A lesser 

 infestation of the same (?) grasshopper invaded the city later, on 

 June 28-29. We may probably safely conclude that small insects 

 were present in unusual quantities in both springs, but that the 

 species were different. (Westward, in the California deserts, at least 

 one butterfly was exceptionally common from November 1957 to 

 May 1958— C. H. Abbott, 1959.) From late March through April the 

 swale habitat was quite well covered with herbs, even on the desert 

 away from the bottoms; most of those flowering in late March were 

 Compositae. Notable among these was a purple-rayed Erigeron 

 which was rare or absent in the desert wash habitat. Also scarce in 

 the latter habitat were grass clumps and weedy Aplopappus-sized 

 shrubs; otherwise, the vegetation there was rather similar to that of 

 the outer part of the swale habitat, dominants being palo verde and 

 Opuntia fulgida, with considerable mistletoe, desert hackberry (most 

 of which had been partly killed back earlier), whitethorn, and low 

 composite herbage, but somewhat less mesquite. 



In the bottom of the swale habitat, the thriving tobosa grass 



