18 Prof. T. D. A. Cockerell on 



piceous, punctured all over ; wings hyaline, faintly smoky ; 

 tarsi with ferruginous hair on the inner side ; abdomen long- 

 mitriform, the segments with entire white hair-bands ; ventral 

 scopa white, black on the last segment and sometimes the 

 hind margin of the penultimate one. 



There are no white hair-marks on the front of the meso- 

 thorax nor at the scutello-mesothoracic suture. 



Superficially resembles M. cleomis, var. lippice, but easily 

 distinguished by the character of themesothoracic punctuation 

 and the much longer second joint of the labial palpus. 



Hab. Mesilla Park, campus of New Mexico Agricultural 

 College, April 16, cutting the leaves of Papains, to use in 

 preparing their nests. 



Megachile vallorum, sp. n. 



? . — Length 14-15 millim. 



Much like M. populi, with the same kind of pubescence 

 and entire white abdominal bands, but differing in many 

 details. Black pubescence arranged on vertex, mesothorax, 

 and scutellum as in M. populi; flagellum wholly dark or 

 faintly reddish beneath ; mandibles with prominent sharp 

 teeth ; second joint of labial palpus a little longer than first ; 

 clypeus with large punctures, dense all over; anterior border 

 of clypeus with a broad shallow emargination, beneath which 

 is a conspicuous fringe of orange hair ; mesothorax densely 

 punctured all over, the areas between the punctures wholly 

 dull ; no white hair-marks on anterior part of mesothorax 

 nor at scutello-mesothoracic suture ; tegulas dark, punctured 

 all over; wings hyaline, broadly smoky on outer margin, and 

 especially at apex ; basal joint of hind tarsi long and flat, 

 considerably longer than the other joints together, covered on 

 inner side with orange-ferruginous hair; spines at apices of 

 first four tibige quite long, dark ferruginous ; abdomen, viewed 

 from above, showing abundant black hair at the sides of the 

 last two segments, but not the others ; ventral scopa white, 

 varying to quite yellowish, black on last segment and apex 

 of penultimate one. 



By the clypeal structure allied to M. montivaga, but other- 

 wise different. 



Hab. Las Cruces (Agnes Williams) ; Mesilla, June 24, 

 entering burrow in an adobe wall (Ckll.) ; Socorro, June 29, 

 two at flowers of a species of Composite (G/cll.). 



Megachile heterodonta, sp. n. 

 ? . — Superficially, in size, form, and colour, even to the 



