190 BRITISH ICHNEUMONS. [ Oroblastus 

Gravenhorst knew three specimens from Gottingen, Breslau in June 
and Geneva; Thomson knew two from Sweden and Oland Island; and 
Gaulle records it from France. It is no doubt rare with us, or at least 
very local; Nunton in Wilts (Marshall) and Norwich (Bridgman). I have 
a full series in Dr. Capron’s collection from Shere in Surrey; and Piffard 
used to take it at Felden in Herts, two of his specimens are labelled 18th 
and 26th June, 1899 and 1900. Desvignes also had two British 
specimens. 
SUB-TRIBE 
CTENISCINI. 
Known from the whole of the Ichneumonidae by having no hind tibial 
calcaria. 
In the Jahresberichte tiber die Fortschritte der Forstwissenschaft und 
forstlichen Naturkunde nebst original-Abhandlungen aus dem Gebiete 
dieser Wissenschaften, 1838, pp. 270-71, Hartig wrote ‘‘ Among the Ich- 
neumons, the genus Z7yphon certainly contains the largest number of 
species which feed on the sawfly larvae. ‘Those species which have no 
terminal spines on the hind tibiae and only one on the middle tibiae I 
unite in the subgenus Z’venferus. In my collection are seventeen species 
here-belonging.” At p. 310, he has a further note dated May, 1838. 
This, then, is certainly earlier than Haliday’s erection of his “ subgenus 
Creniscus, Curt. Guide, No. 492 bis :—Tibiarum Calcaria 1:1:0. Charac- 
teres reliqui subg. Z7yphon,” in the Ann. Nat. Hist., October, 1838. And 
in one of his MS. notebooks, preserved in the Dublin Museum, I have 
seen an entry synonymising his genus with “ven/erus, Htg. In all 
respects but that of the calcaria these insects are inseparable from the 
Tryphonini, though the head is usually buccate, tumidous and the 
abdomen subfusiform. 
Table of Genera. 
(10). 1. Basal segment with lateral margin 
simple, not sinuate. 
(3). 2. Head and thorax densely pubescent ; 
abdomen subpetiolate.. EXYSTON, Schzéd. 
(2). 3. Head and thorax sparsely pubescent ; 
abdomen subsessile. 
(5). 4. Lower mandibular tooth very dis- 
distinctly the longer : .. ACROTOMUS, Holmgr. 
4). 5. Mandibular teeth of equal length. 
7). 6. Hind tibia with minute calcar; ven- 
tral valvulae cultriform .. .. SMICROPLECTRUS, Zhoms. 
(6). 7. Hind tibia with no calcar; ventral 
valvulae not cultriform. 
(9). 8. Second segment impressed; valvulae 
geniculately compressed .. . Dtaporus, Fors?. 
(8). g. Second segment not impressed ; ven- 
tral valvulae simple EXENTERUS, “zg. 
(1). 10. Basal segment with its lateral mar- 
gin trisinuate oe Se : TRICAMPTUS, Fors. 
