MONOGRAPH OF THE NORTH AMERICAN PROCTOTRYriD.E. 81 



scarcely visible from above, or very long, and separated from the me- 

 sonotiim by a strong constriction; mesonotnm not longer than wide, 

 with or without distinct parapsides; scnitellnm generally large, rounded 

 or truncate posteriorily, entirely wanting only in Gonatopus; metatho- 

 rax quadrate or sub(|uadrate, truncate or rounded off behind. Front 

 wings with a lanceolate or ovate stigma, a closed costal cell, two basal 

 cells, and an open radial cell; rarely with a distinct discoidal cell; 

 hiud wings distinctly lobed, veinless except along the costa to tw;o- 

 thirds its length, the tip of this vein being furnished with booklets. 

 Abdomen subpetiolate or petiolate, ovate or oblong-oval, depressed, or 

 occasionally compressed, composed of 8 segments, the ovipositor not 

 exserted. Legs long, the anterior femora much swollen, the middle and 

 posterior pairs obclavate, the tibijiB subclavate, their spurs 1, 1, 2; tarsi 

 5-jointed; the anterior tarsi in the females in all the genera, except 

 Aphclopus and Mystrophoms, are chelate. 



A very interesting group, and evidently an ancient phylogenetic type 

 of the order, the chelate anterior tarsi in the females being found in 

 no other grouj) among the Hymenoptera. 



The Dryimntc confine their attacks to homopterous insects belong- 

 ing principally to the families Fulgorid.e, Membracida^ and Jassidtie, 

 living in felt-like sacks protruding from the abdominal spiracles. 



Prof. Joseph Mik has given a most interesting account of the biology 

 of Oonatopus pilosus Thoms., living on DeUocephalus xanthonciirus, 

 while G. pedestris Dalm. has been reared from Athi/sanus marlUmati 

 and Thamnotettix sulphurella. Aphelopus melaleucus Dalm. has been 

 discovered by Giard, in France, to prey upon Typlilocyha hippocastani 

 and T. douglasi. The genus Lnbeo Haliday, known only in the male 

 sex, bears a superficial resemblance to u^phelopuii and has similar habits, 

 my Labeo typhlocybw having been reared by Dr. Riley from a Typlilo- 

 cyha living on the sycamore. I believe this genus will yet prove to be 

 the opposite sex of Gonatopus. 



The following table will be found all that is necessary to recognize 

 the genera: 



TABLE OF GENERA, 



FKMALES. 



1. Vertex convex, not impreRsed 2 



Vertex deeply impressed ; pro thorax very long ; anterior tarsi chelate. 



Wingless, without a scutelhmi Gonatoi'US Ljuugh. 



Winged, with a scutellum Duyinus Latr. 



2. Stigma oval or ovate 3 



Stigma lanceolate; anterior tarsi chelate. 



Prothorax not quite as long as the mesonotnm, much contracted ; fourth joint 

 of anterior tarsi not much longer than the third, the first twice as 

 long as the three following united; maxillary palpi 4-jointed. 



Boccuus Ashm. gen. nov. 

 21899— No. 45 G 



