17 



It is relatively small and almost spherical in form. Living 

 examples are black, with conspicuous, broken bands of white. 



L. ciliattun, Douglas. Confined to the oak. Adult female approxi- 

 mately circular, moderately convex ; olivaceous brown, ap- 

 pearing greyish from a thin covering of white powdery 

 secretion. It is more particularly characterised by the 

 presence of a fringe of delicate white filaments. 



L. zebrhimii. Green. On the smaller stems and branches of birch 

 and aspen, more commonly on the young trees. Somewhat 

 resembling ciliatniii, but more highly convex and without a 

 marginal fringe. The mature living insect is strongly banded 

 with black on a paler ground, but the pattern is more or less 

 masked by a thin coating of powdery secretion. 



L. hesperidtiiii (Linn.) (fig. 6 a). This is, primarily, a greenhouse pest ; 

 but is occasionally to be found on ivy, myrtle, and holly in the 

 open. It differs from all our other British species in its 

 form, which is flatfish and elongate ovate, and in the fact 

 that it remains relatively soft throughout its life. This con- 

 dition is accompanied by an ovoviviparous habit, in which 

 there is no necessity for a protective covering for eggs. The 

 typical form is of a greenish yellow or orange-yellow colour, 

 minutely specked with darker spots. The variety alienum of 

 Douglas (probably equivalent to laiiri, Sign.) is of a duller, 

 brownish olivaceous tint, closely speckled with darker spots. 

 This variety is not uncommon upon the foliage of the bay 

 {^Laiiriis nobilis). 



The genus I'ldvinaria differs from Leconiinii principally in the 

 presence of a conspicuous ovisac, which is extruded from beneath 

 the posterior extremity of the insect. 



Pulvinan'a vitis (Linn.) (fig. 5 c, (/). On hawthorn, birch, alder, sallow 

 and various species of Itibes. It takes its special name from the 

 fact that it is a recognised pest of the grape vine. The dull 

 brown insect is rendered conspicuous by the snowy white, 

 strongly convex ovisac, which is an accompaniment of the 

 final stage of the female. The small, glassy, male puparia 

 (fig. 5 (/) are sometimes crowded together on the young 

 twigs of the plant. 



In the genus Lichtensia the mature female is almost completely 

 enclosed within a closely felted ovisac, only a small portion of the 

 thorax being exposed. 



L. vibnrni, Signoret. On foliage and young stems of ivy and 

 Laurutinus. The former is the more usual host plant in 

 this country. In the earlier stages it looks like a flat, 

 greenish Lecanium, and is then very inconspicuous; but after 



