372 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 83 



dium", a type of larva originally discovered by Dr. W. M. Wheeler 

 in connection with iiis studies of the eucharid species Orasema viridis 

 Ashmead * and discovered in Perilampus by Harry S. Smith in his 

 studies of the life history and habits of Perilampus hyalinus Say.^ 



KEY TO THE SPECIES OF PERILAMPUS 



1. Frons with a carina extending from behind anterior ocellus 



downward on each side of scrobal cavity to level of insertion 

 of antennae, or nearly to that point; axilla with an elongate, 

 genersUy fingerlike extension running posteriorly along lateral 

 margin of scutellum (if somewhat triangular, then base of 

 extension falling more or less distinctly below middle of 

 axilla) ; surface of axillae above base of fingerlike extension 



more or less depressed or excavated 2 



Frons without such carina or at most with an indistinct one 

 that extends laterad from ocellus for a short distance only; 

 posterior extension of axilla not fingerlike but more or less 

 triangular, its base extending to about middle or above 

 middle of axilla; surface of axillae not depressed 9 



2. Metallic-green, blue, or violaceous species; at least some of striae 



on cheeks continued uninterruptedly onto face; malar groove 

 absent, although rarely faintly indicated; prepectus separated 

 frona pronotum by a very distinct suture; axillae usually in 



part smooth and shining {hyalinus group) 3 



Black species, occasionally in part greenish or bronzj^; striae 

 on cheeks very rarely continuous onto face; malar groove 

 usually distinct; suture separating prepectus from pronotum 

 indistinct; axillae opaque or subopaque, sometimes more or 

 less shining at upper part {platygaster group) 5 



3. Frons laterad of frontal carina witlx longitudinal rugae, without 



large punctures; ocellocular area with transverse rugae; 

 viewed from in front, the frontal carina gradually approaching 

 eye margin, its lower half nearly straight or at least not 

 sharply curved; posterior orbit completely striated or with 

 only a verj^ narrow area smooth, the striae dense and numer- 

 ous. Postocellar line at least about three times length of 

 median line of vertex; scutellum as a rule about as long as 



mesoscutum and prothorax combined hyalinus Say 



Frons laterad of carina with large, shallow, irregular punctures, 

 often more or less wrinkled also but without longitudinal 

 rugae; ocellocular area v.ith coarse punctui-es; viewed from 

 in front, lower half of frontal carina sharply curved toward 

 eye margin; broad area along posterior orbit smooth and striae 

 on cheeks neither dense nor numerous 4 



4. Postocellar line about twice length of median line of vertex, 



distinctly less than twice length of ocellocular line; emargi- 

 nation of frontovertex falling considerably in front of a line 

 tangent to posterior margins of lateral ocelli; scutellum 

 about as long as mesoscutum and prothorax together; head 

 cupreous, face and scrobal cavitj' black, thorax violaceous 

 to blue, antennal fiageUum pale ferruginous regalis, new species 



« Bull. AmcT. Mus. Nat. Hist., vol. 23, art. 1, 1907. 



• U. S. Dept. Agr., Bur. Ent. Tech. Ser. no. 19, pt. 4, 1912. 



