28 BULLETIN 15, UNITED STATES NATIONAL MUSEUM. 



12- to 13-jointe(l, inserted iu a clypeal fovea, the clypeus beiug more or 

 less distinctly cariuated. ProiiottTiu large, well developed, narrowed 

 before; inesouotuiii short, transverse, the scapuhie rarely entirely sep- 

 arated; scutellum subtriangnlar, rarely entirely wanting, the axilhe 

 not separated; luetathorax large, qnadrate. Front wings most fre- 

 quently with a small, stigmated marginal vein (sometimes with a pa- 

 rastigma), a radial and two basal cells, the radial cell rarely distinctly 

 closed; occasionally tlie marginal and radial nervures are wanting or 

 abbreviated; sometimes there is but a single basal cell, rarely en- 

 tirely wanting. Hind wings distinctly lobed, veinless, except along the 

 costa at base. The apterous forms are usually without ocelli and with 

 minute eyes. Abdomen subpetiolate, ovate, or conic-ovate, depressed, 

 composed of 8 segments. Legs rather short, the femora and tibiae 

 stout, most frequently swollen, tibial spurs 1, 2, 2, well developed, the 

 tarsi 5-iointed, the claws often with a tooth within. 



The Bethylincv, so far as we at present know, are ]>arasitic on cole- 

 opterous and lepidopterous larvte, and before pupating most of them 

 spin cocoons. The majority of the genera comprise species winged in 

 both sexes; but in a few genera, viz, Pristoccra, Tsohrachium, Sclero- 

 derma, I>issom2)halns, Agenesia, and Cephalonomia, the male alone is 

 winged, the female, except in Cephalonomia being always apterous. 

 Usually the disparity between the sexes in size and api)earance is 

 such, that, when captured at lai-ge, they cannot be satisfactorily corre- 

 lated. In Cephalonomia a dimorphic form occurs; for, whereas the 

 female is usually wingless and without ocelli, at times a winged form 

 with ocelli is produced. 



The European type of the genus Cephalonomia form id for mis Westw. 

 has been bred in England and Germany from mushrooms infested with 

 coleopterous larva\ In this country species are reared from cyni- 

 pidons galls, infested with coleopterous, lepidopterous, and other 

 inquilines, and it is believed the genus is parasitic on coleopterous 

 larvffi. Species belonging to the genera Isohrachium, Apcnesia, and 

 Pristocera have been taken in ant nests, and it is presumable they are 

 parasitic on myrmecophilous Coleoptera. Ano,vus is parasitic on the 

 coleoj^terous genus Cis living in fungi, and I have reared Ateleopter'ns 

 tarsalis from raisins affected with Silranns surinamenfiis. 



The new genus La'lius is parasitic; on the coleopterous family Der- 

 mestidfe, while species in the genera Bcfhylns, Perisemus, and Goniozns 

 prey upon microlepidopterous larv.T. 



Mr. A. n. naliday, in Ent. Mag. vol. ii, p, 219, has recorded the fol- 

 lowing observation in regard to an unknown Bethylus: 



The insects of this genus seem fond of tho llowers of Syngenesia, but tlieir prin- 

 cipal haunts ar<> in dry sandy districts near the sea. Tho low tufts of Rosa tpino- 

 sissima, flourisJiing among the sand cliifs, supjiort numerous larvae of Tineidie, which 

 when full fed often fall into the little pits of loose saud fornu-d :it tho foot of the 

 clifie by tho gradual scaliug of the bank aild the eddies of wind. These pits are com- 



