166 Mr. J. O. Westwood’s Monograph upon the 
the family to which Stigmus belongs. The connexion between 
Bethylus and Ceraphron, Gonatopus, &c. being so clearly esta- 
blished by means of various fine exotic insects in the Royal 
Museum at Berlin (of which I purpose hereafter laying descrip- 
tions and figures before this Society), that I feel convinced of the 
propriety of regarding Bethylus, Scleroderma, Gonatopus, Sec., as 
belonging to the family Proctotrupiens of Latrielle. This con- 
viction, as regards the genus at present under review, is confirmed 
by the examination of two insects which I have but little doubt 
are male Scleroderma ?. It is true I am unable to state positively 
that this is the case ; but their entire habit and form, the circum- 
stance of their being males whilst females only of Scleroderma 
are known, and our previous acquaintance with the sexes of the 
other chief genera belonging to this family, leave but little doubt 
in my mind upon the subject. These insects may be described 
as follows. 
Characteres generis ex individuis alatis (masculis existimatis) 
desumpti. 
Caput quadratum, angulis posticis rotundatis, depressum, 
thoracis latitudine. Oculi ad angulos anticos, satis elevati. 
Ocelli 3 versus partem posticam capitis. Antennae frontales 
approximate, capite duplo longiores, graciles, 12-articulatae ; 
scapo recurvo, conico, pedicello obconico ; articulis reliquis 
sequalibus. Thorax oblongo-ovatus, collar i antice attenuato ; 
metathorace postice recte truncato. Alee longse, fete ener- 
ves, nervo fere inconspicuo, subcostali, brevissimo, ad apicem 
ejus cum costa coalito, nervum brevem emittente, margine 
alarum ciliato. Pedes satis graciles, femoribus crassioribus. 
Abdomen ovatum, subconvexum, thoracis magnitudine. Color 
insectorum luteus, rufescens, seu fuscus. 
The two male insects which have afforded the above cha- 
racters are described at the end of this Monograph. 
Of the European species of the genus there appears to be 
either a considerable number, as indicated below, or the colours 
and sizes of the species are very variable. From the rarity of the 
insects, it is not possible at present satisfactorily to decide 
whether some of the species described below may not possibly be 
varieties of the others ; certainly, when placed together, they 
appeared to Dr. Erichson (who assisted me greatly in my re- 
searches at Berlin), and myself, to constitute so many species. 
The females of this genus have considerable resemblance at 
first sight to the females of my genus Tlieocolax, with which they 
also appear to be somewhat allied in their subdomestic habits. A 
