Exenterus | BRITISH ICHNEUMONS. 203 

EXENTERUS, Hartig. 
Htg. Jahresb. Fortschr. Forstw. I, P. 2, 1838, p. 270; Cteniscus, Hal. Ann. 
Nat. Hist. 1838-9, p. 113. 
This genus was originally erected independently by both Hartig and 
Haliday in the same year for the reception of all those species of the 
broad genus Z7yphon of Gravenhorst, which possessed ‘no terminal 
spines on the hind tibiae and only one on the middle tibiae.” ‘Thus it 
at first represented the whole Cteniscini and may nowadays be at once 
recognised from the genera more recently detached by having :—The 
lateral margin of basal segment simple and not sinuate, the head and 
thorax not closely and elongately pilose, the mandibular teeth of equal 
length, the hind tibiae with no minute calcar, the ventral valvulae 
neither cultriform nor geniculately compressed, and the second segment 
not impressed. 
The name Cveniscus has been employed for a group of the present 
genus with the body more finely and less rugulosely punctate and less 
coarsely pubescent, the metathoracic areae more complete with areola 
not transverse; but these distinctions intermingle too closely to be of 
generic value. 
I have had considerable difficulty in deciding the priority of the two 
names, since the Jahresberichte is, as I have pointed out in a former 
volume, an extremely rare book in England (if indeed a copy exist, it is 
not in the British Museum), and, since Marshall made no reference to 
such synonymy, the genus has hitherto been known in Britain under 
Haliday’s name, which I am prepared to sink only till such time as the 
exact date of Hartig’s be established. 
Table of Species. 
(30). 1. Areolet of the wing distinct and 
entire. 
(9). 2. Abdomen with no red markings. 
(8). 3. Scutellum more or less flavescent or 
rufescent. 
(7). 4. Hind femora entirely immaculate red. 
(6). 5. Face pale-marked; hind legs stout 
and apically black ra 1. CURTISI, Haliday. 
(5). 6. Face black; hind legs normal and 
apically infuscate . . 2. ELEGANS, Stephens. 
(4). 7. Hind femora entirely black through- 
out : . 3. MARGINATORIUs, fad. 
(3). 8. Scutellum immaculate black .. 4. GNATHOXANTHUS, Grav. 
(2). 9. Abdomen broadly red, at least cen- 
trally. 
(29). 10. Centre of abdomen discally immacu- 
late red. 
(22). 11. Hind femora nigrescent or black. 
13). 12. Scutellum pale-marked 5. PACHYSOMA, SZeph. 
eee 13. Scutellum immaculate black through- 
out. 
(15). 14. Anus entirely fulvous .. 6. PHAEORRHOEUS, /Za/. 
(14). 15. Anus black with the segments ‘usually 
pale-margined. 
(21). 16. Face entirely black or white ; hind 
femora black, 
