388 PROCEEDINGS OF THE ACADEMY OF [July, 



This striking form was taken on the desert plain in the two above 

 locahties where it was extremely scarce. 



DEROTMEMA Scudder. 

 Derotmema laticinctum Scudder. 



On the desert plains of the Papago country this species was collected 

 in numbers, a series of seventy-one males and thirty-three females being 

 before us. It was usually found on exposed areas of adobe soil and asso- 

 ciated with Psoloessa texana. The series is distributed as follows : Tucson, 

 July 26, twenty-seven males, eleven females (one immature) ; Sahuaro 

 slope, southwestern side of Tucson Mountains, July 24, one male; near 

 Sonora Road, southwest of Tucson Mountains, July 25, eighteen males, 

 fifteen females (two immature); Roeble's Ranch, July 24 and 25, 

 twenty-five males (one immature), seven females (two immature). 



This series is quite variable in the depth of coloration and in the 

 character of the maculations on the anal area of the tegmina. Some 

 specimens have three or four comparatively large blotches on this 

 portion of the tegmina, while others have the same region more or less 

 thickly sprinkled with small quadrate blotches. The fuscous bar on 

 the wing varies in intensity and considerably in extent. One speci- 

 men from Tucson has the bar very weak and of httle extent. 



The specimens from the Baboqui vari Mountains previously recorded by 

 the senior author as Derotmema delicatulum,^ prove on second examina- 

 tion and comparison with typical specimens of delicatulum to be this 

 species. The range of the species is now known to extend from the 

 west slope of the Organ Mountains of central southern New Mexico 

 to Phoenix, Maricopa County, and the Baboquivari region, Pima County, 

 Arizona. 



Derotmema delicatulum Scudder. 



This rather remarkable species is represented by four specimens, 

 two of each sex, taken at Sentinel, Maricopa County, July 27. The 

 very prominent eyes, very pale, in fact almost colorless, disk of the 

 wing and much reduced but conspicuous and well-defined transverse 

 blotch on the wing are sufficient to enable one to readily recognize the 

 species. The coloration is very pale, with the darker pattern well 

 defined and comparatively regular. 



The habitat of this form is the Mohave and Ymna deserts, ranging 

 from the western edge of the Mohave at Mohave and Lancaster, Califor- 

 nia, to at least Sentinel, Maricopa County, Arizona. The specimens 



^ Proc. Acad. Nat. Sci. Phila., 1907, p. 72. 



