“THE INTERNAL ANATOMY OF ICERYA PURCHASI. 
Car.L E. JOHNSTON, Stanford University, California. 
The external anatomy, habits and life history of Icerya 
-purchasi are well known through the work of Riley, Comstock 
and others. The present paper contains notes on the internal 
“anatomy of the female, certain details of which depart fram 
any Coccid anatomy previously described. 
This work was done in the Entomological Laboratory ai 
‘Stanford University. 
MOUTH PARTS. 
(Plate XXVIII, Fig. 1.) 
The essential features of the mouth parts of Icerya purchasi 
are the internal chitinous framework, pharynx, and labial 
cavity, the buccal setz, and the external labium. The frame- 
work lies on the ventral body wall in a median line opposite the 
bases of the fore legs, only the posterior ventral side being 
exposed. The bases of the setaze and the pharynx are contained 
in the typical Coccid chitinized box-like structure, lying between 
two indefinitely five-sided areas. The lower plane, or area 
inferior, is considerably the larger. It is bounded on the front 
by the arcus formed by the fusion of the interior end of the 
costae superiores and the coste inferiores, and on the side by 
the right and left coste inferiores, each of these, consisting 
‘of two parts, articulating with it. ' (Pl. XXVIII, fig: 1 b). The 
posterior end of each costa inferior joins with the corresponding 
part of each costa superior to form the clavus. (Pl. XXVIII, 
fig. 1 tu). 
On each side, joining the costz as shown at the point b in 
fig. 1 of Plate XXVIII, and running ventrad toward the costz 
‘superiores, is a chitinous piece, L, which branches just before 
reaching these costae. One branch goes ventrad a short dis- 
tance, lying free in the cavity; the other branch extends a 
little way caudad and serves as a support for the conical base 
‘of one of the sete. 
_ The upper plane, or area superior, is bounded on the front 
by the same fused arcus that bounds the lower area. On the 
sides it is bounded by the costz superiores, each of which 
383 
