28 BULLETIN 45, UNITED STATES NATIONAL MUSEUM. 



12- to 13-jomte(l, iusertetl in ;i clypeal fovea, the dypeua being more or 

 less distinctly carinated. Pronotuni large, well developed, narrowed 

 before; inesonotiini short, transverse, the scapuljB larely entirely sep- 

 arated; scutellum subtriangnlar, rarely entirely wanting, the axilhe 

 not separated; luetathorax large, quadrate. 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 the 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 witn 

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

 comjiosed of 8 segiaents. Legs rather short, the femora and tibije 

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

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



The BethyUncc, so far as we at present know, are parasitic on cole- 

 opterous and lepidopterous larvae, and before i)upating most of them 

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

 both sexes; but in a few genera, viz, Pristocera, Isobrachiimi, Sclero- 

 derma, Bissomphalus, Apencsia, and Cephalonomia, the male alone is 

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

 Usually the disparity between the sexes in size and ajipearauce is 

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

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

 female is usually w ingless and without ocelli, at times a Avinged form 

 with ocelli is produced. 



The Euroi^ean type of the genus Cephalonomia formiciformis Westw. 

 has been bred in England and Germany from mushrooms infested with 

 coleopterous larva?. In this country species are reared from cyni- 

 pidous galls, infested with coleopterous, lepido]>terous, and other 

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

 larvfe. Species belonging to the genera Isobrachitim, Apenesia, and 

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

 parasitic on myrmecophilous Coleoi^tera. Anoxus is parasitic on the 

 coleopterous genus Cis living in fungi, and I have reared Ateleopteriis 

 tarsalis from raisins affected with Silranus )turina7n€n8is. 



The new genus LkUus is parasitic on the coleopterous family Der- 

 mestid«, while species in the genera licthylus, Perisemus, and Gonioziis 

 prey upon microlepidopterous larvje. 



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

 lowing observation in regard to an unknown Bethyhis: 



The insects of this genus seem fond of the flowers of Syngenesia, bnt their prin- 

 cipal hannts arc in dry sandy districts near the sea. The low tufts of Rosa tpino- 

 sistiima, flourishing among the sand cliffs, support numerous larvae of TineidaB, which 

 when full fed often fall into the little pits of loose sand formed at the foot of the 

 cliffs by the gradual scaling of the bank and the eddies of wind. These pits are com- 



