1905.] 271 



THE SPECIES OF TETROPIUM THAT HAVK BEEN FOUND IN 



BRITAIN. 



BY D. SIIAEP, M.A., F.R.S. 



Tetbopium crawshati, sp. n. 



Fere angustum, suhdepressum, nigrum, antennis tihiis tarsisque piceis ; 

 vertire in medio hand, vel vix, depresso ; prothorace vix transversa, vhique 

 crehre, fere cequaliter punctato (i.e., areis IcBvigatis fere nulUs), margine 

 basali ohsulete elevata. Long. 12-16 mm. 



? T. gabrieli, var., Weise, Deutsche ent. Zeitscbr., 1905, p. 136. 

 T.fuscum, Sharp and others, Eiit. Mo. Mag., 1903. 



In addition to the obvious, though slight, characters of form, 

 colour, and punctuation, this species is distinguished from T. luridumhj 

 the more imperfect articulation of the sternal pieces between the middle 

 coxae, and by the (^ genitalia. The thorax is more uniformly punc- 

 tate than in any other of the species, there is no definite longitudinal 

 depression on the front of the head, and the basal margin of the 

 thorax is more obsolete than in either of the other species that are 

 generally known in Europe. There is a slight, but only a slight, 

 difference in the breast of the two sexes, due to the fact that the 

 mesosterum is a little less convex or protuberant beneath in the 

 female. Hence the junction between the meso - and metasternal 

 processes is not so visible in the male as it is in the female ; but in 

 each of the sexes the junction is but imperfectly effected, more 

 imperfectly in the male than in the female. 



This species is named in honour of the Eev. G. A. Crawshay, who 

 has reared a very fine series of it from larch {Lnrix europoea^ at 

 Leighton Buzzard, and who has most liberally presented specimens to 

 the British Museum, and to various individuals in Britain and on the 

 Continent. It is the species recorded by myself as T.fuscum., and 

 has been taken in various localities in this country lying between 

 Norfolk (Atmore) and the New Forest (Sharp, Crawshay, and E. Gr. 

 Smith). The extensive series obtained shows that it is but little 

 variable. It appears to be quite confined to the larch. 



In endeavouring to distinguish the species of Tetropium, there 

 are two characters that should be first examined, viz., (1) the basal 

 margin of the prothorax, and (2) the concavity or the convexity of 

 the front of the head. The species of the mountains of Central 

 Europe, T. hiridum, L., has (1), the basal margin of the thorax 



A A2 



