286 THE ENTOMOLOGIST. 
one, but lies somewhat further removed from the base of the 
wing. In other respects the fly resembles Macquart’s Phytomyza 
nigricans.” Ihave only reared one; the others, doubtless, will 
remain in pupahood till May of next year.—Prrrer INcHBALD ; 
Fulwith Grange, Harrogate, November 10, 1883. 
WATER-BEETLES GUIDED TO WATER By SIGHT, AND NOT BY 
OTHER SENsES.—It is a well-known fact that the water-beetles 
are often found on greenhouses and hotbed-frames, which they 
evidently mistake for water. I have never taken Dytiscus margi- 
nalis in this way, as Mr. McDonald has done (Entom. xvi. 263); 
but I have found small Hydropori on my frames. The habit is 
noted by Professor Westwood in his ‘ Introduction to the Modern 
Classification of Insects’ (1840), where he says (vol. i., p. 103) :— 
 Acilus sulcatus is another species which possesses the power of 
making a noise. Frisch states that this is produced under 
water; but a specimen of the insect which I kept some time (and 
which I had caught on the ground, having fallen whilst flying 
upon some glass-panes, which it had evidently mistaken for 
water) was equally noisy when confined in a box in the sun- 
shine.”—W. W. Fowter; Lincoln, November 7, 1883. 
WATER-BEETLES AND LIGHT REFLECTED BY Guass.—I have 
also, like your correspondent Mr. McDonald (Entom. xvi. 263), 
noticed that water-beetles are often misled by glass, as I have 
found on my frames the large beetles Hydrophilus piceus, as well 
as smaller ones, evidently denizens of the water by their shape; 
indeed I have heard them knock against the glass on fine nights, 
probably travelling between the ponds with which this part 
abounds. This travelling habit of water-beetles may perhaps 
afford some elucidation to the question so often asked as to how 
new ponds, far removed from old ones and having no connection, 
become tenanted with fish and eels, as it seems quite within the 
bounds of possibility that the beetles may carry the spawn 
attached to their bodies —J. Frost; Headcorn, Kent, Nov. 13. 
West Lonpon Enromotogican Socrery Pockret-Box Exaut- 
pitron. — An exhibition of British insects took place on the 
evening of November 16th, in this society’s room, St. Mark’s 
Institute, George Street, Oxford Street. Although called a 
pocket-box exhibition, many of the exhibitors had very properly 
