COLEOPTERA. 



73 



in question is quite a rarity, only three or four examples occurring 

 amongst the hosts oicaesuni examined, and, strangely enough, I did not 

 succeed in discovering any intermediate forms. Therefore, to distinguish 

 this form, I would suggest it be known as ab. mbrujicorne. — Eichakd 

 S. Bagnall, F.E.S., Winlaton. February, 12th, 1906. 



Note on the steidulation of Cychrus rostratus, L. — Six examples 

 of Cychrus rostratus have fallen to my lot since November, 1905, and, 

 on one occasion, no fewer than three 5 s occurred from beneath two 

 stones lying close together. I feel certain that the stridulation of this 

 species is caused by friction between a certain part of the abdomen 

 and the elytra, for, when the beetle stridulates, one can see a slight 

 muscular movement at the apex of the abdomen, and if one holds the 

 insect by the forefinger and thumb, the thumb on the underside of the 

 abdomen and the finger pressmg the elytra down, it seems to lose its 

 power of producing sound. It is generally thought, I believe, that the 

 insect stridulates when disturbed, but two of the six examples above 

 mentioned would not stridulate at all, no matter the amount of 

 disturbance or provocation to which they were subject. Why then, 

 should these two not stridulate like the other four? Examination 

 showed that the four " songsters " were of the fairer sex, whilst the 

 non-stridulators were males ! An interesting point is thus raised. Is 

 the power of stridulation in this species confined to the females, and if 

 so, to what purpose ? Granting the supposition to be the case, it would 

 seem that the female, alone possessing the power of producing sound, 

 would not use that power merely as a means of defence, but rather to 

 apprise the male of her whereabouts. Of course it would be folly to 

 make a definite statement on such slight grounds; C. rostratus, though 

 so widely distributed, is only occasionally met with, and then, as a rule, 

 but single examples occur, thus it is impossible for one to experiment 

 as one would wish, to any great extent ; and I only write this note in 

 the hope that coleopterists, on capturing Cychrus, will, in future, 

 note the stridulating powers in relation to sex, etc., so that in time 

 some definite results may be attained. I shall at once record the 

 stridulation of the male if it be my fortune (or misfortune !) to experience 

 it! — Ibid. [It does not appear to be known for certain where the 

 true organs of stridulation are situated in this beetle. (See Gahan, 

 Trans. ^Knt. Soc. of London, 1900, p. 442). H. J. D.] . 



LiODES, Lat. , A GENUS OF NIGHT-FLIERS. — lu my diary, dated December 

 26th , 1905, 1 notice the following entry : — ' ' Found the ' cast-up ' of a bat 

 in the hollow of an old beech-trunk : composed of a number of Liodes 

 elytra." This beech-tree at one time must have been a veritable forest 

 monarch, and was probably blown down in the great gale which long 

 ago swept the valley, and created such devastation as is difficult to 

 imagine. The shattered trunk is now simply riddled by Sinodendron, 

 and "is affected by hosts of other insects, etc. : it is slightly hollow on 

 one side and is evidently haunted by a bat or bats. The " cast," 

 referred to above, was composed of hundreds of elytra of Liodes humeralis, 

 ling., amongst which I detected a few wing-cases and bodies of what I 

 believe to be L. ylabra, Kug., and also the breast-parts of those and 

 other insects. L. humeralis is not an uncommon beetle in the Derwent 

 Valley, and every now and then a powdery fungus, growing on oak, is 

 found containing a colony of that species ; of L. glabra, I have only 

 taken a single example. It would, therefore, appear from this bat's 



