4 Cincinnati Society of Natural History. 



NATURAL HISTORY NOTES OF SOUTHERN ARIZONA 



By Charles Dury. 



Arizona — That anomalous country, with a fauna and 

 flora so peculiar, and different from other sections of North 

 America; with faunal areas so very unlike each other, even 

 though separated by short vertical distances; where the 

 torrid dry desert of the lowlands is replaced at higher alti- 

 tudes by a climate most delightful, and with peculiar and 

 beautiful vegetation. A study of the desert flora impresses 

 one with the adaptability of many of these plants to unfavor- 

 able conditions, resulting from long periods of heat and 

 dryness. This fierce struggle for existence producing some 

 remarkable modifications of growth. The Giant Cactus, 

 Cereus gigantetis, the Barrel Cactus, Echinocactus Wislizeni, 

 and that amazing Ocatilla Fouquiera splendens, always hold 

 me spellbound by their grotesque oddity. Under the in- 

 fluence of the July rains, the Ocatilla puts forth its second 

 yearly crop of soft, green leaves that mask its array of long 

 and needlelike thorns. Here insect life depends on rainfall 

 as much as does plant life. When the rainy season begins 

 in midsummer, the insect fauna appears like magic. Each 

 species seemingh^ endowed with resistless energy and rapidity 

 of action in the perpetuation of the species. The entomolo- 

 gist who visits this country in the height of the dry season 

 will surely be disappointed. I arrived in Tucson, Arizona, 

 July 7, 1915. The weather was very dry and hot. On the 

 evening of that day I visited the electric street lights in 

 search of insects with no results whatever. There was 

 nothing out. On the afternoon of the 8th, at about 4 p. m., 

 a heavy shower of rain occurred, that lasted over an hour. 

 That evening at 9 p. m., insects were flying around the arc 

 lamps in the streets in swarms. Beetles, bugs and orthop- 

 tera whirled around in clouds. The streets beneath the 

 lights were covered with insects and thousands were crushed 

 by vehicles. Large pale crickets were feeding on the bodies 

 on their mangled fellows. The beetles most in evidence 



