igS BRITISH ICHNEUMONS. {^Pezomachus. 



three times longer than broad ; fifth a little longer than broad. Meso- 

 and meta-thorax of about equal length and both very short ; petiolar area 

 deplanate and oblique, its basal costa wanting. Abdominal pubescence 

 dense and uniform throughout ; basal segment apically broad with its 

 spiracles not projecting ; the remaining segments transverse, with the 

 second and third much shorter than is usual in this genus, and scarcely 

 as deep as the apex of the basal ; terebra a little longer than the first 

 segment. 



Black, with the third antennal joint basally pale and the first abdominal 

 segment apically piceous. Legs lighter or darker piceous, with all the 

 trochanters pale ; apex of anterior femora, the front tibiae and tarsi 

 rufescenl ; base of the intermediate tibiae, centre and apex of the hind 

 tibiae and the hind tarsi, also reddish ; apical tarsal joints infuscate. 

 Length, 2f-3| mm. 



?(?. Head black, palpi piceous and mandibles darker. Antennae 

 piceous, with the apex of the scape and extreme base of flagellum testa- 

 ceous ; latter with the basal joint a little longer than the second, fifth 

 nearly three times longer than broad. Thorax elongate, narrow and black : 

 petiolar area very short with no basal costa. Scutellum distinct and dis- 

 creted. Abdomen elongate-linear, densely punctate, black ; basal segment 

 short, basally broad, tul^ercles obsolete, apex very broad. Legs piceous 

 with apex of trochanters, extreme base of all the femora and apex of the 

 anterior more or less testaceous, as also are the base of the hind, and as 

 far as the centre of intermediate, tibiae ; tarsi entirely piceous. Apterous. 

 Length, 2-3 mm. 



I venture to tentatively associate these two species as sexes of the same, 

 on account of the similarity of the dense abdominal pubescence, broad 

 basal segment which has obsolete tubercles, the absence of the transverse 

 metathoracic costa, black abdomen and piceous legs ; though the brevity 

 of the $ thorax hardly coincides with the length of the male's. Bridgman 

 tells us that the female is closely allied to P. tener. 



He adds that the smaller female was taken at Burford Bridge in 

 September, 1881 ; and the larger bred from the galls of Aulax hieracii 

 in Britain. The male is only recorded from Hastings (Vict. Hist. Sussex). 



17. nigritus, Forst. 



Pezomachtis nigritus, Forst. Wiegm. Arch. 1850, p. 128 ; Voll. Pinac. pi, xii. fig. 3, 

 ? ; Thorns. O. E. x. 1005, i ? . 



? . Head twice broader than thorax, with the genal sulcus deeply 

 impressed and the cheeks not longer than the basal width of the man- 

 dibles ; vertex high and deeply but not broadly emarginate ; clypeus 

 apically truncate ; mandibles not basally tuberculate, and labrum free. 

 Antennae stout and filiform ; two basal flagellar joints of equal length ; 

 the fifth longer than broad. Mesonotum as long as the meta, which is 

 sub-glabrous and nitidulous ; petiolar area of variable length, with its basal 

 costa wanting and surface oblique ; acetabula occupying whole of meso- 

 sternum. Scutellum distinctly indicated. i\bdomen closely and finely 

 punctate and pubescent, dull ; basal segment short and deplanate with no 



