FIELD BOOK OF INSECTS. 



developed; second recurrent nervure strongly bent out- 

 ward in its lower half; tongue flat and bilobed; face pitted. 

 The name of our only genus, Colletes (Plate XCIII), 

 means Plasterer. The species are black, with light hairs 

 but no yellow, chitinous markings. They nest in holes, 

 made in the ground or in loose masonry, and often a 

 number of females nest close to each other. They plaster 

 the sides of these holes, and the cells _which they make in 

 them, with a secretion that dries rapidly to form "a mem- 

 brane more delicate than the thinnest goldbeater's skin, 

 and more lustrous than the most beautiful satin." 



MEGACHILID^: 



In a broad sense, this includes bees having two sub- 

 marginal cells; tip of marginal pointed; second recurrent 

 vein not bent or directed outwardly before joining the 

 first portion of the subdiscoidal vein; face not pitted; 

 tongue long, rather thread-like. The under side of the 

 female abdomen has pollen-collecting hairs, except in the 

 cuckoo genera. The second submarginal cell is much 

 longer than high and almost equal, in length, to the first. 



Stelis includes black bees with whitish margins on the 

 dorsal, abdominal segments, and with cuckoo habits. The 

 tarsal claws are cleft, having an inner tooth near the apex ; 

 male abdomen not toothed or lobed at the apex. Coslioxys 

 (Plate XCIII) is also a lazy genus. The abdomen is 

 narrowed behind, and, in the males, armed with teeth 

 or spines; scutellum usually toothed on the sides; tarsal 

 claws simple or with a basal tooth; eyes, with fine hairs. 

 Both genera have been put in families of their own. 



The industrious members of our Megachilidae have the 

 tarsal claws as described for Ccelioxys. In Dianiliidium 

 (pads between tarsal claws; Plate XCIII) and Anthidium 

 (no such pads) the chitin of the abdomen bears pale mark- 

 ings and in the others it docs not. The former makes 

 nests of resin on rocks, etc.; the latter uses the down off 

 of woolly-leaved plants for nests in burrows. Pleriades 

 (stigma lanceolate, well developed; head considerably 

 extended behind the eyes) and Andronicus (stigma short, 

 not well developed) are black bees with tarsal pads. Osmia 



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