' 
136 Proceedings of the Royal Physical Society. 
| gg of H. ater. | oe . 
The egg of H. ater calls for no special comment. It is oval in shape, 
_ shining white in colour, and shows neither sculpturing nor micropyle. It 
measures ‘9 mm. long and ‘54 mm. in diameter. The eges of H. nea 
and H. cunicularius do not differ from that of H. ater. | yan 
i 
Larva of H. ater, (Plate X. Figs. 20— 25.) 
In general appearance this larva is a curved, white, fleshy, legless grub, 
with wrinkled body and well-marked yellowish head. It is made up of 
fourteen segments including the head, which forms the first segment. The 
next three segments form the thorax, and the remaining ten the abdomen. 
All the body segments are somewhat similar in shape and size, except the 
ninth and tenth abdominal. The ninth is smaller than the others, while 
the tenth segment is reduced to form the anal lobes. The first thoracic and 
the first eight abdominal segments each bear a pair of Piacee The 
thoracic segments each bear a pair of foot-calli or pads. 
For the sake of brevity further description of ° the larva may. a 
omitted ; the accompanying figures of the H. ater larva, it 1s hoped, will serve 
to take its place. I have been unable to obtain any satisfactory characters 
for the identification of species in the larve of the genus Hylastes, although 
I have examined large numbers of the larve of the three species under 
consideration. 
Pupa of H. ater. 
The pupa of H. ater calls for no special comment. It is naked and free, 
and shows all the parts present in the adult beetle. The abdomen terminates 
in a pair of spiny processes. The three species, H. ater, H. palliatus, and 
Hf, cunicularvus, can readily be distinguished in the pupal as in the adult 
stage by the configuration of the thorax. 
HABITS AND LIFE-HISTORIES OF THE Tur EE SPECIES. 
Habitat. 
All the three species of Hylastes under consideration attack conifers. 
H, ater breeds in the roots of the Scots pine, and feeds either on similar 
roots or on young conifers of various species below soil level. Its egg, 
larval, and pupal stages are spent in Scots pine roots oe trees from twenty 
to seventy years of age. 3 
H. cunicularius breeds in the roots of spruce, where its egg, larval, and — 
pupal stages are spent, and feeds on similar roots or on the roots of other 
young conifers, like its congener H. ater (Fig. 28), 4 
