ICHNEUMONID/E. TROGUS. 269 



Sp. 1. crassitarsus. Niger, abdominis medio, tibiis anterioribus, femoribus, 

 cajiitisque piduris rufis. (Long. corp. 3 — 4 lin. ; Exp. Alar. 5 — 7 lin.) 



Sc. crassitarsus. Gravenhorst, ii. 360. — Steph. Nomen. 2d edit. Gen. 717. 1. 



Black : head tawny-rusty, with the crown, occiput, sometimes a dot beneath 

 the antenniE, and 2 lines on the face black ; antennae rusty, dusky towards 

 the base, the 1st joint black above, yellowish beneath ; abdomen a little de- 

 pressed, slightly channelled, black, the apex red, 2nd and 3rd red, remainder 

 black, with the base of the 4th slightly reddish ; anterior legs testaceous- 

 red, C0XE8, trochanters, and extreme base of the middle femora black, 

 posterior with the femora red, the tibiae reddish at the base, the apex 

 blackish ; tarsi rather thick and black ; wings rather smoky-hyaline. 

 Taken very rarely, in July and August, within the metropolitan 



district. 



Genus XLVIII.— TROGUS, Paji-zer. 



Antenme moderate, about half the length of the body, setaceous, porrect, or 

 curved at the apex, sometimes faintly serrated within : head short, transverse, 

 a little narrowed towards the collar : eyes oval : thorax gibbous : scutellum 

 somewhat quadrate, more or less gibbous : wings rather ample, in the 

 British species transparent ; celhde 3-angular or 5-angular, sessile, or 

 somewhat petiolated: abdomen petiolated, convex, oblong, or oblong-ovate, 

 the anterior portion of the 1st segment somewhat gibbous, generally with 2 

 elevated lines, peduncle slender, linear and channelled : ovipositor concealed: 

 legs moderate, femora and tibise rather stoutish. 



The splendid insects, contained in this fine genus, may be distin- 

 guished not only by their great bulk, but chiefly by having the 

 scutellum very convex, the abdomen distinctly pedunculated and 

 convex, and the head transverse ; their larvae usually prey upon 

 those of the Sphingidse, or of the larger Bombycidae and Noctuidae : 

 from the splendid series I possess of these insects, and from their 

 habit, &c. I am induced to consider that Gravenhorst has confused at 

 least 3 distinct species together, as I have attempted to indicate. 



Sp. 1. alboguttatus. Niger, abdomine ccerulescente, segmenti 1-mi margine ef 

 segmenti 7-imi lined longitudinali albis, scutello albo : mas facie albomaculata ; 

 foemina annulo antennarum albo. (Long. corp. 6^ — 9 lin.; Exp. Alar. lOg — 

 \5\ lin.) 



Tr. alboguttatus. Gravenhorst, ii. 374 — Steph. Nomen. 2d edit. Gen. 718. 1. 



Black : palpi of the male, 2 spots on the clypeus, a dot on the mandibles and 

 cheeks, and the inner orbits ochreous-white, or with the entire clypeus 

 white, and the face white, with a black spot; antennae of the same sex 

 porrect, a little serrated within ; of the female red at the tip, with the 11th 



