1918.] 245 



We especially noticed, in corroboration of Mr. Champion's state- 

 ment, the extreme variation in their size and their remarkable agilit}^ 

 for our shadow falling on one settled on a log or stump was quite 

 sufficient to make it instantly take to wing, thus making their capture 

 exceedingly difficult. 



This infatuation of the Melmtophila for a situation which suggests 

 the precincts of Tartarus, is of course no novel discovery. Mr. Champion 

 quotes (Ent. Mo. Mag. 1913, p. 109), from a paper by Mr. A. H. Mann, 

 the almost exactly parallel case of M. notata Lap. & Gory in N. Caro- 

 lina ; and the publication of the observation of a similar habit of another 

 MelanopJiila in India by Mr. H. Gr. Champion in the September 

 issue of this Magazine was curiously coincident with our experience of 

 31. acuminata here. 



Now the interest of this narration lies, perhaps, not so much in the 

 evidence it affords that this beetle is extending its range in the South of 

 England, as in the biological problems which it evokes. We must, in 

 the first place, certainly admit that M. acuminata offers a remarkably 

 good example of cryptic protective resemblance, for the wrinkled dull $ 

 or somewhat shining 6 elytra so exactly match the charred surface of 

 the pine bark on which they usually rest that detection until they move 

 becomes almost impossible. 



Thus we may explain its morphology and colour, but not the 

 development of the singular attraction which heat has for the insect. 

 That of simply charred wood is a different matter, and such insects 

 as Pterostichus angu-^tatus, Acjonum ^--punctatum, ^pJiaeriestes, and 

 others, may find in such places conditions which are favourable to their 

 own larval existence because they have been cleared by former heat of 

 other subcortical enemies or competitors. 



But no such factors are involved in the attractive influence of heat 

 alone. We found pairs of this beetle "in cop." on timber whose com- 

 plete destruction by fire seemed imminent, — and if oviposition took place 

 in such a situation it is evident that instead of any advantage a very 

 serious risk of a similar fate would be run by any resulting progeny. 

 One can only conjecture that the females flew to some safer spot, where 

 although the trees might be charred they were not actually alight, before 

 they commenced to deposit ova. The utility therefore in the ontogeny 

 of the beetle of the heat attraction still remains unexplained, and as such 

 I must leave it. 



" The Bungalow," Crowthorne, Berks. 

 October Ith^ 1018. 



