tttE CiNAblAN ENTOMOLOGlSt. 



insects in Britain, Only the female sex is known, and it is believed that 

 the winged Ichneumons assigned to the genus Hemiteles, of which no 

 females are known, are the males of Pezomachus. Repeated efforts have 

 been made to place this beyond doubt, but they have usually failed, for 

 when a brood of these parasites is reared the individuals generally prove 

 to be either all Hemiteles or all Pezomachus. It is to be hoped that this 

 interesting case will be fully elucidated." Of the American species 

 assigned to Pezomachus, several are known in both sexes. Mr. 

 Howard, for example, describes both $ and (J of P. micarice (Proc. 

 Ent. Soc, Wash., Vol. II., p. 194), bred by Mr. Emerton from the egg- 

 cocoons of a species of Micaria. Individuals of P. Pettitii vary some- 

 what in colour and in shape of thorax, the anterior node of which is often 

 sulcate, as in Provancher's type of sulcatiis. Nearly all those taken in 

 the field have the abdomen entirely dark, except the apex of first segment, 

 while all the bred specimens have the apex of second segment also pale. 

 The winged males appear slightly larger than the wingless, and have the 

 abdomen slightly more elongate, but its markings are exactly the same. 

 The fully developed thorax is black, and the wings have a large triangular 

 stigma of a dark brown colour. The antennse are darker, and apparently 

 more slender. 



I 



Pezomachus ottawaensis, n. sp. 



Female, length, 5-6 mm. Rufous, with abdomen in part black. 

 Head transverse, slightly narrowed behind ; occiput concave ; antennas 

 long and rather slender, 23-jointed ; face subtuberculate, as also clypeus 

 slightly ; mandibles sometimes paler, with the teeth black. Thorax 

 binodose, the nodes subequal ; the rounded metathorax not areolated, 

 but with the posterior face flattened obliquely. Abdomen with a broad 

 rufo-orange band covering nearly all the second segment, the petiole also 

 rufous ; the second segment narrowly black at base, and the following 

 segments black, polished; ovipositor exserted about i mm., sheaths black 

 at tip. 



Described from 23 females bred, with two exceptions, from egg- 

 cocoons of spiders. This is a large, handsome Pezomachus, very con- 

 stant in coloration, especially of the abdomen. The base of petiole, 

 posterior coxae, and femora are darker in a few specimens, and the vertex 

 of head is occasionally clouded ; individuals may possibly occur with the 

 head in part black. The egg-cocoons in which this species breeds are 



