196 { February, 
CONTRIBUTIONS TOWARDS A KNOWLEDGE OF THE LIFE-HISTORIES 
OF CERTAIN COLEOPTERA. 
I.—DeEnproruaGus crenatus, Payk. 
BY F. BUCHANAN WHITE, M.D. 
With the exception of a description by C. von Gernet in the Hore 
Soe. Ent. Rossicz, vol. vi, 1868 (Beitrige zur Kaferlarvenkunde, zweiter 
Beitrag, p. 19), of two larvee supposed to belong to this species (but 
which were not reared), very little seems to have been written regard- 
ing the life-history of this rare and interesting beetle; probably, for 
the best of all reasons, that very little is known. Having perhaps a 
more intimate acquaintance with it than any one else in Britain, I am 
glad to be able to throw a little more light on the subject. 
The larva has been supposed by some to be carnivorous, but it is 
truly phytophagous, feeding on the inner layer of the bark of dead 
trees of the Scotch-fir (Pinus sylvestris), and more rarely of the Larch 
(Larix europaeus). The perfect insect lives in the same situations, pre- 
ferring places where the bark is rather loose and cracked. In such 
places it remains quiet during the day, resting either upon the bark or 
upon the wood, but, when disturbed, it runs off with considerable ce- 
lerity. Towards night-fall, the beetle seems to come forth from its 
hiding-place, as at least in one instance it has been captured “ coursing 
rapidly, towards evening, over a bare fir log” (E. C. Rye, HE. M. M., 
ul, 68). 
In the perfect state, Dendrophagus has been captured in May, 
June, July, August, and September ; and, though I am not aware that 
it has been observed, it probably passes the winter in the perfect state, 
the specimens taken in May, June, and July, having probably hiber- 
nated. As, however, Jarve of different sizes are to be met with through- 
out the summer, it is possible that the spring specimens of the beetle 
may have been recently excluded from the pup, though all my speci- 
mens emerged in August. 
Larve have been noticed in every month from May to September; 
and frequently larve of different sizes (and probably, therefore, of 
different ages) were found at the same time and place. Further 
observation is required before the duration in the larval state can be 
ascertained. It is not improbable, however, that it continues for at 
least one year, if not longer. Some larve, at least, hibernate when 
nearly of full size. The duration of the pupal state is from a fortnight 
to three weeks. In August, soon after their exclusion from the pupa, 
several specimens were observed iz cop. I did not succeed, however, 
