141 



and fruit trees which blossom later. The antennas are black, 

 and the green body is covered with fine white hairs, becoming 

 yellowish above. 



In the Harris collection are the cells and specimens of Osmia 

 pacifica Say, the peaceful Osmia, which, according to the man- 

 uscript notes of Dr. Harris, is found in the perfect state in 

 earthen cells (Plate 5, Fig. 2) beneath stones. The cell is oval 

 cylindrical, a little contracted as usual with those of all the spe- 

 cies of the genus, thus forming an urn-shaped cell. It is half 

 an inch long, and nearly three-tenths of an inch wide, while the 

 cocoon, which is rather thin, is three-tenths of an inch long. 



The following genera, called Cuckoo Bees, are parasitic on 

 other bees, laying their eggs in the cells, or nests, of their host. 

 In Codioxys the body is stout, and the bee closely mimics its 

 host, Megachile. The ligula is very long, being almost three 

 times the length of the labium, and the paraglossse are wholly 

 wanting ; the maxillary palpi are short, three-jointed, and the 

 abdominal tip of the male is variously toothed. Codioxys octo- 

 dentata Say, is abundant late in the summer about flowers. An 

 allied genus, Melecta, is parasitic on Anthophora, and Epeolus is 

 parasitic on Colletes. 



The species of Nomada are very numerous ; in all, the tongue 

 is long and acute, with paraglossa? about one-fourth as long 

 as the tongue ; the maxillary pair of palpi are six-jointed ; 

 and there are three subcostal cells. The species in their slen- 

 der, smooth, gaily colored body resemble the wasps. These 

 Cuckoo-bees lay their eggs in the nests of Andrena and Ha- 

 lictus, and, according to English authors, Panurgus and Eucera, 

 where they may be found in all stages of development corre- 

 sponding to those of their hosts. The females do not sting 

 severely. The species emit sweet, balmy, or balsamical odors. 

 Shuckard states that these bees should be killed with burning 

 sulphur to preserve their bright colors. 



The larvie differ greatly from those of their hosts, Andrena, 

 the head being much smaller, the body being smoother and 

 rounder, and belonging to a more degraded, lower type. The 

 whole body is more attenuated towards both extremities. 

 The pupa differs from those of any other genus of this family 

 known to us, except Audrena, by having three conspicuous 



