170 Mr. E. Saunders' remarks on the hairs of some 



is very striking, for, in some species they are simple, in 

 others rigid and branched, in others ligid, straight and 

 spirally grooved, in others branched and flexuous ; and 

 these different styles of pollen hairs occur in species the 

 metathoracic hairs of which may be almost identical : for 

 instance, in Megachile, Osinia and Chelostoma the hairs 

 of the metathorax are very similai", but in Megachile the 

 pollen-brush of the abdomen is composed of beautifully 

 rigid spiral hairs ; in Osmia, of simple ones ; whereas in 

 Chelostoma they are long and flexuous, with branching 

 filaments. 



The following varieties of hairs, I think, may be easily 

 distinguished : — 



1st. Simple hairs occurring occasionally on various 

 parts of the body and on the scopre of some 

 species oi Andrena, &c., and the pollen-brush 

 of Osmia and Antliidium (fig. 1). 



2nd. Simple hairs, with a slight swelling above the 

 base, occurring on the scopas of Andrena 

 albicans, 2, &c. (fig. 2). 



3rd. Rigid, straight, spinose hairs, spirally grooved, 

 forming the pollen-brush of Megachile, post 

 tibife oi Andrena albicans, $, &c. (fig. 3). 



4th. Serrate or very shortly-branched hairs (to be 

 found on the thorax and body of most of the 

 species), the apices of the branches in the 

 hairs of the scopfe of Dasgpoda, ? , are more 

 or less clubbed (figs. 4, 16). 



5tli. Hairs with long branches (to be found in every 

 variety — the most beautiful round the meta- 

 thorax of Colletes, Eucera, Apis, Sec.) (figs. 

 5,6). 



6th. Rigid, somewhat spinosely-branched hairs (scopjB 

 of 3Iacropis, &c.) (fig. 7). 



7th. Long flexuous hairs, with branching filaments 

 (pollen-brush of Chelostoma, floccus of A7i~ 

 drena, &c. &c.) (figs. 8, 9). 



8th. Somewhat rigid hairs, with one or two short 

 tooth-like branches near the apex or with 

 several branches mostly projecting on one 

 side, sometimes almost fan-shaped (tibia3 of $ 

 and ¥ Andrena albicans, Colletes cunicularia, 

 and most of the Andrcnida (figs. 10, 11, 12, 

 12a). 



