132 HYMENOPTERA. 



much narrowed towards the marginal, the third slightly so ; the 

 posterior tibiae and the basal joint of the tarsi furnished with a 

 thin scopa of long pubescence. 



1. PTILOTHRIX PLUMATUS. 



Female. Length 5 lines. Black, the clypeus and labrum 

 have large scattered punctures and are thinly clothed with 

 griseous pubescence, above the insertion of the antennae and on 

 the cheeks it is dense, short, and dark fuscous ; the flagellum 

 ferruginous beneath, tips of the mandibles yellow. Thorax, the 

 disk densely clothed with short fulvous pubescence, thinner and 

 paler on the sides ; the legs red, the coxae black ; the anterior 

 coxae and femora fringed with black pubescence ; the interme- 

 diate and posterior coxae and trochanters fringed with cinereous 

 pubescence ; on the anterior tibiae and tarsi above, and on the 

 posterior tarsi within, it is fuscous, otherwise the legs have a glit- 

 tering pale yellowish pubescence, having a little which is snow- 

 white at the apex of the posterior tibiae ; wings hyaline, and 

 having a yellowish tinge towards their base, tegulaa and nervures 

 pale rufo-testaceous. Abdomen ovate, the base fringed with 

 short fulvous pubescence ; the margin of the first and three fol- 

 lowing segments has a broad fascia of very short decumbent 

 pubescence, broadest in the centre ; the two apical segments 

 covered with rigid black pubescence. 



Obs. This beautiful species is remarkable for having the entire 

 pubescence plumose, each individual hair being pectinate ; that 

 on the metathorax, viewed under a pocket lens of good power, 

 resembles fine down ; even the short pubescence which forms the 

 fascia on the abdomen is equally beautiful. 

 Hab. Brazil. (Coll. F. Smith.). 



Genus 8. ROPHITES. 

 (Details, Plate V.) 



Rophites, Spin. Ins. Lig. fasc. 2. no. 50. p. 72- 



Dufourea, St. Farg. Hym. ii. 228. 



Halictoides, Nyland. Ap. Boreal. Act. Soc. Sc. Fenn. i. 195. 



1. ROPHITES QUINQUESPINOSA. B.M, 



Rophites quinquespinosa, Spin. Ins. Lig. fasc. 2. p. 72. no. 5. 



Latr. Gen. Crust, et Ins. iv. p. 161. 



Encycl. Meth. x. 312. 1. 



Rophites spinosus, Nyland. Eevis. Apum Boreal, p. 235. 1. 

 Hab. France; Italy. 



