LECANIUM NIG BUM. 



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yellow, polygonal derm-cells, but the angles are so 

 rounded that they appear more or less ovate ; the space 

 between the cells very dark brown or black, forming a 

 distinct reticulation; when viewed by transmitted 

 light the derm-cells (Fig. 5, a) are seen to have a 

 central, clear pore or nucleus, and the angles of the 

 cells appear less rounded than when seen from above. 

 Dermis at the margins without derm-cells or reticula- 

 tions. Marginal hairs (Fig. 5, fe) small, simple ; and 



FIG. 5. Lecanium nigrum, Nietn., ? : a, polygonal derm-cells, x 140; b, 

 marginal spine, x 600; fefe, inner marginal spines, x 600; c, antenna, 

 x 140 ; d, leg, x 140 ; c, claw with digitules, x 300. 



just within the margins are a few more or less divided 

 hairs (Fig. 5, lib) connected with tubular spinnerets. 

 Antennae (Fig. 5, c) normally of seven joints, of which 

 the fourth is the longest and constricted towards the 

 apex, from which arises two long hairs ; there is also a 

 stiff, spine-like hair on the fifth and sixth joints ; 

 formula 4, 3, 7, 2, 1 (5, 6). Exotic examples have 

 sometimes eight- jointed antennae, when the formula is 

 3, 8 (1, 2, 4, 5), (6, 7). Legs (Fig. 5, d) slender; digi- 



