234 BRITISH ICHNEUMONS. yPezomachus. 



brachial cell ; nervellus opposite, and the areolet pentagonal with its outer 

 nervure wanting 



Black ; base of antennae, second, third and apex of first segments red 

 or somewhat infuscate. Legs testaceous, with the hind tibiae apically 

 nigrescent. Wings sub-hyaline, with the stigma basally white. Length, 

 3-5 mm- 



Schmiedeknecht says the c^ legs are black, with the tarsi, tibiae and 

 anterior femora partly testaceous, with the apices of the posterior tibiae 

 black. 



Besides that of van Vollenhoven, there is a figure of the $ in Wood's 

 " Insects at Home," pi. x. fig. 2. 



Smith tells us (Trans. Ent. Soc, 1859, p. 210) that he bred four females 

 from their own oblong cocoons in a single nest of Agelena bnitinea in the 

 middle of June, 1859 ; subsequently twenty-two specimens were bred 

 from seventy-three nests, in only one case four and in six cases three from 

 a nest, and whenever the parasite emerged no trace of live spiders remained. 

 Heiniteles formosus appeared from these nests in about equal numbers, but 

 always singly, and four or five spiders always subsequently developed from 

 the same nest. " It appears to me," he adds, " that the fact of the Pezo- 

 machiis feeding upon the spiders and not on the Hemiteles is clearly proved, 

 as, in the latter case, spiders as well as Pezomachus ought to have been 

 developed" (cf. Bridgman, under P. zonatiis, ante), "and when we take 

 into consideration the fact of Pezomachus being quite as bulky an insect as 

 Hemiteles, it can scarcely be supposed that the larva or pupa of the latter 

 could afford nourishment to three or four larvae of the former." Both 

 sexes of the Hetniteles emerged, precluding an idea of sexual affinity, unless 

 under greatly dimorphic conditions, which the gregarious and solitary 

 habits of the species appear to finally preclude. 



This is one of our most abundant species, though, like P. instabilis, 

 it occurs almost exclusively on low herbage. Common in Norfolk ; fre- 

 quently bred from Apanteles cocoons (Bridgman), and from nests of 

 Agroeca briimiea (Giraud and Bridg.) ; Bickleigh and Exminster ; and 

 twice bred in Devon in the middle of July from the egg-bags of spiders, 

 Lycosa pullata (Bignell) ; common at Glanvilles Wootton (Dale, who also 

 records it from Harris in the Hebrides) ; occurs at Fairlight, Dallington 

 and Peppering, in Sussex (Vict. Hist.); Shere in Surrey (Capron). Both 

 sexes in Dorsetshire ; male bred from the egg-sac of a species of Theridion 

 (Pickard-Cambridge, Entom. 1881, p. 137) and examined by me. Both 

 sexes parasitic on Microgasteridae (Entom. 1881, p. 139) — these are repre- 

 sented in Bridgman's collection, labelled " Bred from Microgaster nest, 

 Norwich, Sep., 1880." Bramford, near Ipswich (E.M.M. 1900, p. 42); 

 taken in the Carlisle district (Day); Deal marshes in July (Sladen) ; on 

 the sea-shore, near Weymouth (Richardson) ; Lake District (Bowdler) ; 

 Hendon in January, and Barnby Broad (Elliott) ; Scotland (Dalglish) ; 

 Thornton in Fife (Evans) ; Isle of Mull (Tomlin) ; Retford (Thornley) ; 

 Felden (Piffard) ; Appledore, Whitby, Church Stretton, Kilmore and 

 Enniscorthy (Beaumont) ; New Forest (Miss Chawner) ; Shere in Surrey 

 (Capron) ; Knovvle and Boxhill (W. Ellis) ; Southwold and Norton Wood, 

 in Suffolk (Tuck). It has occurred to me during every month of the 



