Other analogous species attack the leaves of the Oak, Elm, 

 &c., for a similar purpose *. 



LlTHURGUS, Lat., 



Where there are four joints in the maxillary palpi, as in the follow- 

 ing subgenus, but the abdomen is depressed superiorly. All the 

 joints of the labial palpi are placed end to end f , and the palpi them- 

 selves resemble long squamous setae, terminating in a point. The 

 mandibles are narrow in both sexes, and their extremity is emar- 

 ginated in the middle or bidentated. The females have a rounded 

 projection in the middle of their head %. 



OsmU, Panz. — Anthophora, Fab. — Trachusa, Jur., 

 Where the maxillary palpi are formed of four joints, or at least of 

 three very distinct ones, and the abdomen is convex above. Some 

 are masons, and frequently have two or three horns on the clypeus, 

 which appear to be of use to them in the construction of their nests. 

 They conceal the latter in the ground, holes in Avails, doors and old 

 wood, and sometimes even in the shells of Helices, employing an 

 earthy mortar for their construction. They are generally pilose, and 

 appear early in the spring. The antennae of the males are usually 

 long. Others employ the petals of flowers, and form cells with the 

 cut portions, in the manner of the leaf-cutters. The Abeille tapis- 

 siere of Reaumur forms its cells with the petals of the Avild Poppy, 

 and sometimes of the Rape §. Others again form their nests in the 

 galls of trees 1|. . . 



Anthidium, Fab., 

 Where the abdomen is also convex; but the maxillary palpi are uni- 

 articulated. The females form their nests with the down of plants ^. 

 The two last subgenera of the Dasygastrse approach the following 

 ones in the absence of a silken brush, a fact which Avould lead us to 

 suppose that these Insects are equally parasitical ; but their labrum 

 is parallelogramical, and their mandibles are triangular and dentated. 

 The maxillary palpi are very short and biarticulated. 



Stelis, Panz. 

 The scutellum destitute both of spines and teeth. The abdomen is 

 nearly semi-cylindrical, convex above, and curved at the extremity**. 



CcELIOXYS, Lat., 



Where the scutellum has two teeth or spines, and the abdomen is 



* Lat., Gen. Crust, et Insect., IV, p. 165. 



t The third joint is usually inserted on the outer side of the second, anterior to its 

 point, and with the second forms a little oblique and lateral stem, 



X Centris cormta, Fab., and an undescribed species from the Isle of France. 



§ This species, with all those in v/hich the mandibles are tridentated, forms the 

 genus Anthocopa of M. Lepeletier. See Encyc. Method., article Rophyte. The 

 OsmiiE, properly so called, have but two teeth in each mandible. 



li Lat., Gener. Crust, et Insect, IV, 164 ; and the Encyc. Method,, article Osmie. 



^ Lat., Ann. du Mus. d'Hist. Nat, XIII. 



** Lat,, Gener. Crust, et lasect., IV, 163. See particularly the Encyc. Method,, 

 article Stilide, 



