86 HYMENOPTERA. 



half the length of the mcntum ; the paraglossae a))Out half the 

 lengtli of the lahiuni ; lahial ])al])i four-joiuted ; maxillary palpi 

 six-jointed, the hasal joint of the former as hmg as the three fol- 

 lowing ; the maxillary have all the joints of about equal length ; 

 the wings as in the genus Halictus. Abdomen in the females 

 furnished with an anal rima. 



Obs. M. Gucrin has indicated the separation of these insects 

 from the genus Halictus, and has proposed the name Aguposte- 

 mon, but without giving the generic characters. 



1. AgAPOSTEMON NIGRICORNIS. B.M. 



Andi-ena nigricornis, Fabr. Ent. Stjst. ii. 313. 28, 3 • 



Andrena vLrescens, Fabr. Ent. Syst. ii. 314. 29, $ {Mus. Dotn. 



Banks.). 

 Centris nigricornis, Fabr. Syst. Piez. p. 360. 33. 



Cocqueb. Illus. t. 25. f. 7- 

 Megilla virescens, Fabr. Syst. Piez. p. 333. 23. 

 Hub. Mount Pleasant, Ohio; "Wilmington, Delaware. (E. 



Doubleday, Esq.) 



2. Agapostemon tricolor. B.M. 

 Hahctus tricolor, St. Farg. Hym. ii. 289. 33, <? . 



Hab. N. America; Mount Pleasant, Ohio. (E. Doubledav, 

 Esq.) 



3. Agapostemon .eruginosus, n. s. B.M. 



Female. Length 5 hnes. — Golden-green, the abdomen more 

 or less tinged with blue ; the face roughened with confluent 

 punctures ; the cly]ieus most strongly rugose, its apical margin 

 as well as the labrum and mandibles mfo-testaceous, the latter 

 ferruginous at the tips ; the flagellum rufous beneath. Thorax 

 truncate, finely roughened by confluent punctures ; base of the 

 metathorax not enclosed, strongly rugose ; wings rufo-hyaline, 

 the tegula; and nervures i)ale testaceous, the inner margins of 

 the former green, apex of the wings clouded ; legs rufo-testa- 

 ceous, their pubescence beneath fulvous, on the intermediate and 

 posterior tibiae above fuscous. Abdomen ovate, very minutely 

 and closely punctured ; the basal margins of the second, third 

 and fourth segments depressed, sparingly covered with short gri- 

 seous downy ])ubescence, which is longest and most dense at the 

 sides ; the fifth and apical segment covered with dark fuscous 

 pubescence ; beneath rufo-testaceous, having a green tinge, mar- 

 gins of the segments fringed with fulvous pubescence. 

 Hab. St. John's Blufl^, East Florida. (E. Doubleday, Esq.) 



I 



