BRITISH ICHNEUMONS. 13 



white, with white hairs ; apically sub-striate. Abdomen bluish-black, 

 depressed ; c?, at least, with third and following segments transverse and 

 finely alutaceous ; post-petiole explanate and margined or hi maculated 

 apically with white, somewhat rugose with rounded angles and bisinuate 

 apically ; second and third segments narrowly red-margined ; the segments 

 with a dorsal depression ; seventh centrally white, in ? with a longitudinal 

 basal carina ; ventral fold flavous. Legs slender, pubescent, black ; apex 

 of anterior femora and part of coxae, all the trochanters, tibiae and tarsi, 

 except apex of hind ones, stramineous, darker in ? . Wings somewhat 

 clouded ; tegulae black ; radix and base of costa, white ; stigma reddish or 

 fuscous. Length, 12-16 mm. 



The capital markings are somewhat variable, but the genal patch and 

 apical band of first segment are very distinctive. 



This species is said to be common in Britain, though Stephens tells 

 us it used to be not very abundant, though found occasionally, in June, at 

 Darenth and elsewhere about London, as well as in Devonshire, the New 

 Forest, Norfolk, Salop, &c. Bignell has bred it from Orgyia pudibiaida^ to 

 which it appears to be nearly confined in Britain, in the middle of June, in 

 South Devon ; and Mr. Waterton has given me an example from the above 

 host in southern England about the same date. Beaumont has specimens 

 from Bury St. Edmunds, and it has been taken at Bishop's Wood, York- 

 shire, early in August. On the Continent, where it is common, it has also 

 been bred from Thyatira batis, Liparis aurijlua, and Bombyx vionacha. 

 The host's cocoon sent me by Mr. Waterton is expanded to its fullest 

 capacity, and the parasite emerged through a very jagged semicircular 

 incision towards the capital extremity, but the operculum is not removed 

 as is usually the case in the emergence of Ichneumons ; within the parasite 

 had spun no vestige of a cocoon for itself. Bignell, in Buckler's " Larvae," 

 says Mr. R. Adkin once bred this species in Britain from Sphinx ligustri. 



TROGUS, Panzer. 

 Panz. Kril. Revis. ii. So (1S06) ; Forst. Ver. pr, Rheinl. 1868, p. 188. 



Head slightly tumidous ; cheeks and temples sub-buccate ; mandibles 

 obtusely bidentate, the lower tooth somewhat the shorter ; clypeus apically 

 a little dilated ; labrum shortly exserted. Antennae of $ more or less 

 dilated beyond centre. Thorax robust, longer than high, punctate ; 

 notauli very distinct ; metathorax short, basal sulcus profound ; spiracles 

 elongate. Scutellum elevated, sub-pyramidal. Abdomen oblong or oblong- 

 ovate, apically obtuse ; segments truncate, with no distinct aciculations or 

 foveolate impressions ; terebra short, scarcely exserted. Legs normal. Wings 

 large and stout ; arcolet rhomboidal ; radial nervure apically incurved. 



As Stephens remarks, these insects are extremely variable in colour, 

 upon which no reliance can be placed : in some examples the thorax is 

 nearly black with various rufescent markings, in others it is red with various 

 black markings ; the abdomen may be entirely testaceous or the four 

 apical segments deep black throughout ; the legs also are very inconstant 

 in colour. Stephens included Ichneumon flavatorius^ I. luteiventris and 

 his own T. dissimulator in this genus on account of their large size and 

 sub-convex scutellum. 



