132 HYMENOPTERA. 



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

 ))osterior tibia- and the basal joint of the tarsi furnished with a 

 thin seopa of k)ng pubescence. 



1. Ptilothrix plumatus. 



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

 have large scattered punctures and are thinlj- clothed with 

 griseous pubescence, above the insertion of the antenna and on 

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

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

 disk densely clothed with short fulvous pubescence, thinner and 

 paler on the sides ; the legs red, the coxa? black ; the anterior 

 coxa? and femora fringed with black pubescence ; the interme- 

 diate and ])osterior coxte and trochanters fringed with cinereous 

 jjubescence ; on the anterior tibia; and tarsi above, and on the 

 jjosterior 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 tibia? ; wings hyaline, and 

 having a yellowish tinge towards their base, tegulse and uervures 

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

 short fulvous ])ubescence ; 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 

 jjubescence plumose, each individual hair being pectinate ; that 

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

 resembles fine dovai ; even the short pubescence which forms the 

 fascia on the abdomen is equally beautiful. 

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



Genus 8. ROPIIITES. 



(Details, Plate V.) 



Rophites, Spin. Ins. Liff. 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. 



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



Encycl. Meth. x. 312. 1. 

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

 Hab, France ; Italy. 



