HELIX HORTENSIS. aon 
M. Rathay remarking on the habit of ascending the beech, ash, alder, 
and other trees, finds that this is done for the purpose of feeding upon the 
micro-alga, Pleurococeus vulgaris, clothing their bark, and that the wavy 
browsing tracks can be traced to a height of thirty feet or more from the 
ground ; it is, however, probable that the Plewrococcus is not the only 
nourishment obtained, as it is passed through the body almost intact. 
Fic. 391.—Feeding tracks of 7. hortensis, and probably other species, showing the appearance 
produced by their browsing upon the Plewrococcus growing on the trunks of trees (after Rathay). 
Parasites and Enemies.—//elix hortensis is preyed upon by the 
same enemies that are so destructive to the preceding species, suffering 
in common with it from the attacks of rats, mice, hedgehogs, rabbits, 
and other mammals. 
It is also a favourite food of blackbirds, thrushes, and other birds, and 
its shell fragments are often very common around the ‘“‘thrush stones,” 
striking relics of avian rapacity. 
Drilus flavescens L., a beetle in which the male, though comparatively 
very small, is winged, while the female, which was regarded as a distinct 
species by Meilzinsky and named Cochleoctonus vorax, is large and 
apterous, being in reality only a slightly metamorphosed larva, and 
although very closely allied to the glow-worm, is not at all luminous. 
It is very destructive in its perfect and larval stages, destroying numbers 
of H. hortensis, H. nemoralis, ete., taking up its abode within the shell, 
while devouring the inhabitant. 
WW, ME ——e Drilus flavescens L., showing 
me Pe ae a Le . three of its phases of existence, 
ee : j AC ys" in all of which it is destructive 
= lancet = oR “SY sto the present and allied species. 
Len ry [Y 7 \. Fis Fic. 392.—The diminutive winged male, 
| Lb 9) 3 ; x 4 (after Spry and Shuckard). 
# | hye er} se Fic. 393.— The large apterous female, 
| J : slightly reduced (after Spry and Shuckard). 
} Nx Sy Fic. 394.—The active larval stage,slightly 
modified and reduced (after Westwood). 
3] 
\ / 
“NS 
Fic. 392. Fic. 393. Fic. 394. 
Mr. E.G. Bayford has graphically described the aspect and habits of 
the larva, a specimen of which he received on Sept. 5th, 1905, from Deal. 
It was scolopendroid in shape, and eighteen mill. in length and two mill. 
