226 FOREST ENTOMOLOGY. 



3 mm. long, bearing upon its back the singular square-shaped excresc- 

 ences, which are composed partly of secretion and partly of the effete 

 skin of the previous moult. The latter is not cast off, but splits or 

 divides into squares, and these, as the insect grows, become more and 

 more widely separated. In May another moult takes place, the newly 

 cast skin carrying with it the marginal fringe and all the old exuviaa 

 and secretion. After the final moult the insect grows somewhat 

 rapidly," and the period of fecundation is therefore reached. 



Later on the female at the parturition period assumes a chestnut- 

 brown colour, with a highly convex swelling in the central area. The 

 whole scale retains slight traces of the original waxy covering, with a 

 shining surface and a fringe of delicate hairs at the outer margin of 

 the scale. 



The antennae usually consist of eight joints, but this number is not 

 always constant, as seven is often found. The legs are comparatively 

 short, with unusually well-developed coxse. 



Lecanium bituberculatum (Targioni-Tozzetti). 



The adult female scale of this species is a large, brown, highly con- 

 vex scale, with two pairs of sub-dorsal shining tubercles projecting 

 considerably beyond the contour of the scale. It is found on haw- 

 thorn hedges, more especially in the eastern and southern parts of 

 England, but it is very local. It has several characters which go to 

 determine it as a distinct species, but these are of more importance to 

 the specialist in scale-insects than to the general student of forest 

 entomology. It is, however, one of the most beautiful and best 

 marked of all the British species. 



Lecanium CAPREiE (Linn.) 



This insect may be called the common brown scale of the forest, as 

 it is found on quite a variety of food-plants viz., hawthorn, apple, 

 elm, sycamore, oak, alder, willow, hazel, lime, horse-chestnut, laurel, 

 wild sloe, &c. (see fig. 209). Careful observation and comparison of 

 similarly aged specimens will show that this scale varies very much 

 in form according to the food-plant. Thus on elm and horse-chestnut 

 the insects are smooth and spherical, while on lime and hawthorn 

 they are more flat, slightly elongated, and wrinkled. During life the 



