CHALCID FLIES OF GENUS PERILAMPUS — SMULYAN 383 



PERILAMPUS PLAT YG ASTER Say 



Perilampus platigaster Say, Boston Journ. Nat. Hist., vol. 1, p. 274, 1836. — 

 LeConte, The complete writings of Thomas Say on the entomology of 

 North America, vol. 2, p. 722, 1859. 



"iPerilampus platygasier Provancher, Petite faune entomologique du Canada et 

 particulierement de la province de Quebec, vol. 2, Hymen., p. 572, 1883. — 

 ViERECK, Connecticut State Geol. Nat. Hist. Surv. Bull. 22, p. 524, 1916. 



Female. — Length about 2.5-3.5 mm. Head: Froiis with a promi- 

 nent carina extending from behind the anterior ocelhis downward on 

 each side of the scrobal cavity to or beyond level of insertion of 

 antennae, sometimes reaching nearly to level of ventral margin of 

 eye; frons laterad of carina and ocellocular area usually in large part 

 distinctly shagreened ; emargination of frontovertex narrowly arcuate 

 and not widening rapidly downward, the distance between lateral 

 ocellus and nearest point on carina about equal to or shorter than the 

 shortest distance from this point to anterior ocellus, when longer 

 usually not considerably so ; apex of emargination touching or slightly 

 cutting line tangent to anterior margins of lateral ocelli; postocellar 

 Hne distinctly or considerably longer than median line of vertex (not 

 so pronounced in the males); scrobal cavity deep, its sides sloping 

 steeply, the steep slope continued more or less to level of base of 

 clypeus so that hyperclypeal area appears relatively considerably 

 depressed; eyes with a dull surface; face at sides of clypeus rugulose 

 or rugose or rugose-granular (usually coarsely granular) ; malar furrow 

 present but sometimes weak and rarely, in the males at least, prac- 

 tically absent or merel}'^ indicated ; clypeus as a rule about as long as 

 wide and about one and one-half times to nearly twice as long as 

 hyperclypeal area (in one male more than twice as long), anterior 

 margin of clypeus medially faintly arcuate, the basal margin usually 

 slightly arcuate; cheeks convexly rounded, the striae on same not 

 crossiag malar furrow onto face; head in front view transverse; eyes 

 reaching to or below level of base of clypeus (latter condition gen- 

 erally more pronounced in the males). 



Thorax: Walls between umbilicate punctures on mesoscutum and 

 scutellum thin, mere septa (on the latter sometim.es slightly thickened 

 along median longitudinal line); area along inner margin of parap- 

 sidcs distinctly and completely or practically completely shagreened; 

 suture separating prepectus from pronotum indistinct; axilla with an 

 elongate fingerlike extension running posteriori}'- along lateral margin 

 of scutellum, the base of this extension falling more or less distinctly 

 below middle of axilla; face of axilla more or less excavated imme- 

 diately above base of extension, the portion immediately anterior to 

 extension not sloping toward latter; surface of axilla completely or 

 practically completely sculptured and opaque or subopaque and as 

 a rule without very conspicuous rugae immediately above base of 

 extension; basal shallow furrows on underside of apex of scutellum 



