264 BRITISH ICHNEUMONS. 



than long, its apical margin straight or a little rounded, immarginate, and 

 abruptly depressed throughout ; mandibles bidentate, lower tooth short ; 

 face somewhat convex centrally, and not or hardly discreted from the 

 clypeus. Antennae filiform, or a little attenuate apically ; scape often 

 inflated, deeply and obliquely excised at the apex. Metathorax not pos- 

 teriorly produced, its areae complete. Abdomen elongate-fusiform or, in 

 S, linear; central segments very finely alutaceous ; second not striolate, 

 with thyridii somewhat remote from base; terebra a little exserted. Legs 

 normal ; hind coxae of ? usually simple. Areolet complete ; nervellus 

 always intercepted obviously below the middle. 



This genus has hitherto been merged in Britain in Phaeogenes, since 

 Wesmael subsequently considered its characters insufficient to warrant 

 generic rank, and in this he was followed by Marshall, and, later, by 

 Bridgman and Fitch. On the Continent, however, it has been universally 

 accepted, and is now well established by the additional characters indicated 

 above. 



Table of Species. 



(2). I. Thyridii remote from base of second 

 segment; thorax red -marked (Thy- 

 RAKELLA, Hohiigr.) J. COLLARIS, Grav. 



(i). 2. Thyridii approximating base of second 

 segment ; thorax not red-marked dis- 

 cally (DiADROMUS, auctt.). 



(4). 3. Head normally buccate ; scutellum api- 

 cally white I. TROGLODYTES, Craz/. 



(3). 4. Head strongly buccate ; scutellum black. 

 (12). 5. Lower mandibular tooth normal ; (J with 



face and coxae not white. 

 (11). 6. Petiolar area more or less impressed; 

 scape not entirely fulvous. 



(8). 7. Thorax entii'ely black ; $ hind coxae 



cristulate 2. SUBTILICORNIS, Grav. 



ij). 8. Thorax of $ not entiiely black ; coxae 

 mutic. 

 (10). 9. Face and thorax not white-marked 3. VARICOLOR, IVesm. 



(9). 10. Face and thorax white-marked ... 4. guttulatus, 6^n?7/. 



(6). II. Petiolar area not impressed ; scape en- 

 tirely fulvous 6. CONCILIATOR, JVesm. 



(5). 12. Lower mandibular tooth very short ; (J 



with face and coxae white 5. candidatus, 6'nzz'. 



I. troglodytes, Grav. 



Ichneumon troglodytes, Gr. L E. i. 587 ; Ste. III. M. vii. 202, ? . Diadromus troglo- 

 dytes, Wesm. Nouv. Mom. Ac. Brux. 1844, P- 207 ; Bui. Ac. Briix. 184S, p. 329, ? ; lib. 

 cit. 1855, P- 43i> i ' Holmgr. Ichn. Suec. iii. 3S5 ; Thorns. O. E. xv. 1631 ; Berth. Ann. 

 Soc. Fr. 1S96, p. 35S, 6 9. 



Head hardly narrowed posteriorly, black ; vertex not dilated ; frons dull 

 and closely punctate ; palpi and mandibles pale ; S with sides of face and 

 usually the clypeus stramineous. Antennae apically sub-attenuate, red, 

 more or less black above ; of $ with scape beneath, of $ with central 

 band, white ; those of ? hardly reach beyond thorax. Thorax shining, 

 black ; $ with callosities at radix white ; areola hardly longer than broad, 

 apically truncate ; petiolar area slightly impressed. Scutellum with usually 

 a white sub-apical fascia. Abdomen narrow, red with first segment black, 



