276 BULLETIN 45, UNITED STATES NATIONAL MUSEUM. 



ISORHOMBUS Fiirst.'i. 

 Hym. Stu<l., II, p. 107 (185«). 



Head transverse, the vertex tlatti'iied, tlie oeeijuit with a sharp mar- 

 gin; ocelli 3, trianfjuhuly arranjied, the lateral far aAvay from the 

 marjjiii of the eye or nearer to the front oeellns than to the eye niarj^in. 



Antemue inserted. jnst above the clypens, 10-joiiited in both sexes, in 

 5 terniinatiiifif in a .'*>. jointed chd), in S with a 5 jointed elnb, the .joints 

 of which are longer than thi<'k. the first fnniclar joint very niinnte. 



Thorax ovate, the i>rothorax distinct, the niesouotuin much longer 

 than wide, with furrows, the scutellum subconical or subpyramidal, «'ud- 

 ing in a little spine at tip, and more or less pubescent, the metathorax 

 short, with a median carina. 



Wings when folded extending to, or a little bevond, the tip of the 

 abdomen, pubescent and veinless. 



Abd<>men long, in $ pointed ovate, in S oblong-oval, the first seg- 

 ment longer than wide, the second very large, occupying fully two- 

 thirds of the whole surface. 



Legs clavate, the basaljiiint of hind tarsi twice as long as the second. 



Distinguished by the 3 jointed club in the female, the shape of the 

 scutellum, the long mesonotum, and the position of the ocelli. 



Isorhombus hyalinipeunis Ashm. 



(PI. xii, 2,J.) 



Can. Eut., xix, ji. 11*9 ; Cress. Syn. Hym., p. 249. 



5. Length, 1.5""". Black, shining, impnnctured, the occiput alone 

 finely transversely aciculated; antenna", excejtt the 3-jointed club and 

 legs, brownish-yellow or yellow; the coxa' and club black. Head trans- 

 verse, the lateral ocelli about their width from the border of the eye, 

 the mandibles and i)alpi pale (»r yeHowish. 



Antenna; lO-.iointed; scape subdavate, as long as the pedicel and 

 funide united; i>edicel not quite as long as the first and second fnniclar 

 joints united; second fnniclar joint very little longer than the first; 

 third and fourth small, transverse; fifth much wider, transverse; club 

 3-jointed, black, the joints loosely joined, the first two subcjuadrate, 

 very slightly serrate toward one side at apex, last joint oblong. Tho- 

 rax convex, without furrows or oidy slightly indicated i>osteriorly, the 

 little lobe thus formed i)ro.jectiug slightly upon the scutellum. Scu- 

 tellum subconvex, foveated at base and with oidy a slight tubercle at 

 tip, the tubercle being subobsolete. Metathorax and petiole subpu- 

 bescent. Wings hyaline. Abdomen ovate, depressed, polished, im- 

 punctured, the petiole scarcely as long as wide. 



S. Length,!"". Differs only in tho antemue, the club being 5-, 

 jointed, pale, the first and third fnniclar joints small, the second being 

 stouter and about thrice as long as thick. 



Habitat. — Jacksonville, Fla. 



Types in Coll. Ashmead. 



