Xyhnumius.] BRITISH ICHNEUMONS 19 



The 9 . like all profusely marked Ichneumonidae, varies somewhat in 

 coloration; (^ravenhorst instances two varieties, the first with the head and 

 thorax and abdomen varie<;ated with red and white, and the second with 

 face and scutellum entirely white. 



This species, the female of which is of the size and outline of 

 X. irrigator, differs from A', pilicornis in its variegated head and thorax, 

 and basally white tibiae, the $ in its shorter and more densely pilose 

 antennae, and immaculate abdomen. 



This disctinct species, which is very rare in Sweden and not recorded 

 from Belgium, was first described by Fabricius from specimens, taken at 

 Halle in Prussian Saxony, in Hiibner's collection. Gravenhorst took several 

 females at piled timber in Germany ; and Ratzeburg tells us that he found 

 it several times preying upon Callidium sanguineum in hornbeam logs, as 

 well as perhaps Tctropium luridum ; Thomson says it has been bred from 

 a species of Col/uiiiim at Lund ; and Brischke raised it from Callidium 

 variahile. Though all these Longicorn beetles are British, none of them 

 are at all common with us and it is consequently not surprising that there 

 are no records of indigenous breeding ; Desvignes introduced this 

 parasite as British on the strength of both sexes in his own collection, in 

 1856, but the only other notice of it I can find is my own mention (E. M. 

 M. 1903, p. 2g) of two females, taken together in a garden in Lyndhurst, 

 in the New Forest, where Callidium violaceiim is often abundant, on 

 20th August, 1 90 1. They were flying in the morning, beneath glass 

 affixed to a brick wall for the preservation of fruit trees ; and in these 

 instances the antennae have the apical four joints subclavate and distictly 

 setiferous, with the basal metathoracic area reduced to a single broad 

 carina. 



2. rusticus, Desv. 

 Xylonoiuus rusticus, Desv. Cat. 122, ? . 



Head black ; clypeus with short rufescent pilosity. Antennae hah 

 length of the body and aj)ically reflexed. Thorax cylindrical, black ; 

 metathorax punctate, unequally bidentate on either side, with the 

 areae hexagonal. Abdomen sub-cylindrical and immaculate with the 

 three basal segments punctate ; the first longer than the second and third 

 combined, with a transverse impression before its apex ; second and 

 third a little broader, former with gastrocaeli distinct and a small fovea 

 on either side behind the centre ; fourth and seventh of equal length, 

 fifth and sixth shorter ; third to fifth ventral segments plicate ; terebra as 

 long as the body, "inserted in the fifth, colour red ; the ovipositors in the 

 terminal abdominal segments ; the apexes of the whole a little dilated, 

 but ending in a sharp point." Anterior legs testaceous with the coxae and 

 apical tarsal joint darker, femora basally slender and compressed and 

 apically distinctlv dilated, their tibiae internally obliquely impressed, 

 apically intumcscent, constricted and tortuous towards the base ; hind 

 legs black and simple with the coxae elongate and castaneous beneath, 

 trochanters very short. Wings infumate-hyaline and basally testaceous ; 

 tegulae, stigma and costa infuscate. 



An examination of Desvignes' two 9 9 hi the National collection 

 enables me to add: — Head cubical, hardly broader than long and laterally 

 parallel behind the eyes ; vertex glabrous and very strongly nitidulous 

 with a very few scattered punctures ; frons distinctly, evenly and not 



C2 



