320 PROTECTION AGAINST INSECTS. 



beneath the orbicular spot (claviform stigma). These mark- 

 ings are constant in position, but some or all of them may be 

 absent. The body is thick, and usually covered with down ; 

 the head surrounded by a collar. Flight nocturnal or during 

 twilight, hardly ever by day. 



Caterpillars usually bare, rarely hairy, commonly with 10 

 prolegs, sometimes with 8 or 6. 



Pupation of the bare caterpillars generally takes place in the 

 ground, in a cocoon made of grains of sand bound together by 

 a few threads. The hairy caterpillars spin a cocoon above 

 ground. Pupae usually slim, spindle-shaped and dark coloured. 

 Many of the caterpillars live on woody plants, eating needles 

 and leaves, but the majority of them feed on grasses and low 

 plants. A few species are highly injurious to forests. 



f 



Fig. 163. Nocliia piniperda, Panz. (Natural size ; fig. c enlarged.) 

 a Male, b Female, c Eggs on a pine-needle, d Caterpillar, c Pupa. 



1. Noctua piniperda, Panz. (Pine Beauty, or Pine Noctua). 

 a. Description. 



Moth with a wing-expanse of 35 mm. ; fore- wings russet-red 

 marbled with grey ; orbicular and reniform stigmata yellowish- 

 white, conjoined, the latter large, oblique and produced towards 

 the tip of the wing ; hind-wings and abdomen greyish-brown. 



Caterpillar 40 mm. long, with 16 legs, almost hairless, of a 

 yellowish-green, with 3 or 5 whitish-coloured stripes and a 

 light-brown head. 



