THE ANNALS 



AND 



MAGAZINE OF NATURAL HISTORY. 



[SEVENTH SERIES.] 



No. 90. JUNE 1905. 



LXVIIT. — Some Bees of the Genus Melissodes /?'o/m the 

 Rocky Mountain Region. By T. D. A. Cockerell. 



The following table separates a series of comparatively 

 large females, all 12 mm. oi' more in length : — 



Hair on inner side of basal joint of hind tarsi 



black or almost 1. 



Hair on inner side of basal joint of bind tarsi red. 4, 



1. Smaller, witb more convex, black, very shiny 



abdomen ; hair of labrum pale reddish ; 

 middle of thorax above naked; eyes pale 



greenish grey glemooodensis, Ckll. 



Larger, with flatter, less conspicuously shining 

 abdomen; pubescence of thorax more 

 ochreous 2. 



2. Hair on labrum pale ; thorax hairy, or over- 



lapped with hairs, in middle above ; eyes 



pale reddish ; abdomen conspicuously banded. MizetB, Ckll. 



Hair of labrum dark or brownish 3. 



3. Smaller, hair of pleura all light blakei, Ckll. 



Larger, hair of lower part of pleura dark .... chrysothamni, Ckll. 



4. Size very large ; facial quadrangle not broader 



than long helianthelli, Ckll.*. 



* The following characters are also useful: — 

 ^Yings strongly yellowish; stigma entirely 

 ferruginous. 

 Second submarginal cell much broader above 



than its height helianthelli. 



Second submarginal cell much narrower above 



than its heiglit Martini. 



AVings not strongly or not yellowish ; stigma 



with at least the lower part darkened , . . ; all the other species 



in the table 



Ann. ^- Mt'j. N. Hist. Ser. 7. Vol xv. 35 



