.LECANIUM HESPERIDUM. 79 



yellow at the margins ; immaculate (fig. 3) or irregularly 

 spotted with dark reddish brown or brownish black, the 

 spots frequently forming an irregular network, the 

 meshes of which are much more pronounced in the central 

 and abdominal areas (fig. 10), appearing to the naked 

 eye as two transverse patches or bands. As the insect 

 matures and the period of parturition begins, the 

 reticulations coalesce, the patches or bands unite, 

 and the dor sum becomes wholly dark brown, approach- 

 ing to black (fig. 4) ; finally the margins change to a 

 brownish colour (fig. 5), and the insect dies. After 

 death the insect is usually either dusky yellow or pale 

 brown, but the dorsum generally retains its dark 

 colour. Form slightly convex and elongate, narrowed 

 more or less anteriorly, with the cephalic extremity 

 generally curved to one side, rendering the outline of 

 the body much less curved on one side than on the 

 other ; but occasionally the curvature of the sides is 

 more or less equal (fig. 5) ; dorsum usually with a faint 

 keel. After death the margins become irregularly and 

 transversely wrinkled. Antennae (fig. 6) of seven 

 joints, of which the third, fourth, and seventh are the 

 longest; there is a very long hair on the second, a 

 slightly shorter one on the fourth, and there are several 

 on the terminal joint ; formula (3, 4), 7, 2, 1 (5, 6). 

 Legs (fig. 7) slightly longer than the antennae, with a 

 long hair on the trochanter. Derm-cells (fig. 8) small, 

 ovate, and widely separated. Marginal hairs (fig. 9), 

 either simple or dilated at extremity, and variously 

 serrated. 



There is a slight variation in the antennal joints, 

 but not to the marked extent I find in several other 

 species of Lecanium. 



With regard to the differential structural characters 

 set forth by me in 1891,* in my endeavour to separate 

 L. lauri from L. hesperidwn, I now find that specimens 

 vary inter se, and are quite inseparable. 



Male. In his description of Chermes lauri (1. c.), 



* ' Ent. Mo. Mag./ vol. ii, s.s., p. 245. 



