28 



size (Fig. 5 represents the largest specimen we have seen) it may be 

 distinguished from the 3 of iiciimocgciii by the close proximity of 

 costal spot and band, which in rare instances actually touch. The ex- 

 tent of the fulvous area in the 9 is greater than in the other species 

 of the group, the basal area being at times even more extendedly yel- 

 low than shown in Fig. 6. The underside of the secondaries in both 

 sexes shows, as Skinner has noted, a more extended and better defined 

 whitish banding. The color of the upper side may vary from pale 

 yellow to deep orange-yellow, the 9 sex especially being in this re- 

 spect more variable than the $ . 



The Claw Segment (PI. Ill, Fig. 12), apart from size, is much 

 as in neumoegcni. The pulvillus is, however, truncate and not conical. 



Genitalia. The S clasp (PI. V, Fig. 7) is of the same type as 

 in neumoegeni, but the terminal hook of the Blade is decidedly longer 

 and narrower ; the Proharpe is very strongly toothed ; rather longer 

 than in the allied species and midway between aryxna and neumoegeni 

 in the breadth of its base. 



The Uncus (PI. Ill, Fig. i) is broader and shorter than in neu- 

 moegeni, and the lateral incision at the base somewhat deeper; the 

 Gnath is not so long and much broader than in the allied species. 

 The Penis (PI. VI, Fig. 11) is curved, with a subapical group of 6 

 minute teeth on each side of the central opening. 



In the 9 the Vaginal Plate (PI. VI, Fig. 3) possesses marked 

 similarity to those of the other members of the group; the chitinous 

 folds around the vaginal orifice are more complicated and somewhat 

 more raised; the inner margin of the Alae projects downwards to- 

 wards the apex of the Lateral fold; in form the Alae are semi-cylindri- 

 cal, with a small chitinous flap projecting over and covering the distal 

 portion. 



The species is evidently abundant in certain localities, as we have 

 received during the past two years more than 100 specimens about 

 equally divided as regards sex. 



Habitat: S. Arizona (Redington, Santa Catalina Mts., Baba- 

 quivera Mts.) (Sept.-Oct.) (M. Chrisman). 



Group II 



Thoracic clothing appressed and rather sparse. $ without long hair at base 

 of secondaries. 

 M. vuccAE Bdv. 

 Eudamus yuccae Boisduval & LeConte, Lap. Am. Sept. PI. 70 (1833). 



