246 THE ENTOMOLOGIST. 



from my friend, Professor Westwood, at Oxford, but without 

 any notes, except that the twigs were from the willow ; I re- 

 ceived at the same lime a quill containing some imagos, both 

 male and female, produced from the galls. 



I conclude that this is the species described by De Geer 

 in his 'Memoirs' (German translation, vol. ii. p. 271 et seq., 

 pi, 39, f. 1 — 11), and by Dahlbom in his ' Clavis novi 

 Hymenopterorum Syst.' (p. 28, No. 38), and called by the 

 latter Nematus Peniandrce, mihi, with a reference to Lin- 

 naeus' * Fauna Suec' (ed. 1, num. 943.) According to both 

 these writers more than one larva is contained in these galls, 

 that is to say, two, three, or four, or even five living together ; 

 they remain in tliis state until the end of April, when they 

 change to pupae, still within the gall. The larvae are greyish, 

 and toward the end of that stage they acquire a purplish tinge. 

 The cocoons are thin, and of a coffee-brown colour. The 

 pupae are greyish while with a purple linge ; those of the 

 male are suialler than the pupae of the female ; the eyes, 

 though probably only towards the end of the pupa stale, are 

 dark red. The imagos, it seems, appear in the middle of 

 May ; they gnaw a circular hole in the gall, through which 

 they make their escape. 



The following is the description of the imagos which were 

 sent to me : — 



Male. — Length, 5*5 millim. Shining black, with an ex- 

 tremely short and fine whitish pubescence on the head and 

 thorax. Head somewhat more protruding than in the former 

 species, and destitute of grooves. Trophi and cheeks very 

 pale brown, except the tips of the mandibles, which are 

 shining black ; palpi pale brown. Upper lip pubescent. 

 Antennae not more than half the length of the body, thick ; 

 the joints sharply divided from each other and thickened 

 below ; the first two joints black, the others brown, darker 

 towards the base on the upper side. Thorax narrower than 

 the head, very shining on the sides, with brown tegulae. 

 Wings iridescent, nervures black ; stigma black, with the ex- 

 ception of a brown spot at the base. Abdomen narrower 

 than the thorax, shining black, with the exception of the 

 anal valve, which is of a brown tint. Coxae black nearly 

 to the tip, apophyses pale brown ; femora blackish at the 

 base and thence brown, of which colour are the tibiae and 

 tarsi, except the posterior tarsi, which are blackish. 



Female. — Somewhat smaller. Exactly similar to the male, 

 with the following exceptions: — The antennae are shorter, 



