ae EXPLANATION OF TERMS. 
Dimerous. Two-jointed. 
Dorswm. The upper side of the body when the insect is in its natural position. 
Dorsal. On the upper side or dorsum. 
Eyes. Two coloured, granular or simple, round organs on the cephalic region of 
the female, near the base of the antenne (Plate xiv., Fig. 2, k.; Plate 
xx., 6); two, or four, coloured, granular, simple or facetted, on the head of 
the male (Plate i., Figs. 14,15; Plate xxi., Fig. 2, 0). 
Femur. The second joint of the feet, next the coxa, joined to it by the false 
joint “trochanter.” (Plate i., Figs. 6 f, 7 f.) 
Fringe. A portion of the excreted substance, cotton or wax, produced by the 
spinnerets on the edge of the body in certain Lecanidine and Hemi- 
coccidine. It may be in the form of long glassy threads alas a or of 
more or less broad flat plates (Ctenochiton). (Plate vii., Figs. 2d, 8a; 
Plate xii., Fig. 2, a, b, c.) 
Haltere. A minute organ, situated just behind the wings of the males, and of 
which the use, either in this family or in the Diptera, has not been satis- 
factorily ascertained. It is often termed the “balancer.” In the house-fly 
it has been thought to represent an organ of hearing. In Coccids it is 
furnished with one or more hooked bristles, and Mr. Comstock affirms that 
these are, probably for some purposes of flight, hooked into the posterior 
edges of the wings.* (Plate i., Fig.17; Plate xxi., Fig. 1, 7.) 
Honeydew. A substance of a glutinous character produced by many species, and 
falling in spray from them on the leaves. (See Chap. III.) 
Larva. The first stage in the insect’s life after emerging from the egg 
Lobes, in the Diaspidine, are minute, flat, more or less rounded projections, two 
or more, seen on the edge of the abdominal extremity, usually interspersed 
with spines and hairs (Plate ili., Figs. 1, 3, 4, 5, 2); in the Lecanidine, are 
two triangular or conical projections, usually bearing hairs, on the dorsal 
side of the body, one on each side of the abdominal cleft (Plate x1., Fig. 3, 
OO) 
Mentum. A kind of secondary rostrum, or ‘‘ under-lip,” not altogether tubular, 
but rather a deepish trough, through which the rostral setz pass after leav- 
ing the rostrum. It may have one, two, or three joints. It is not noticeable 
in the Diaspidinz. (Plate i., Fig. 5, 0.) 
Metamorphosis. A change ofform. For the number and characters of these see 
Chap. IT. 
Moniliform. Like a string of beads. 
Monomerous. With a single joint. 
Multilocular. With several divisions: a term applied to the spinneret orifices 
of some insects, distinguishing them from “simple” orifices, which show 
only a single tube. Maultilocular orifices exhibit a bundle of tubes enclosed 
together. (Plate i., Fig. 4, c,d, p; Plate xviii., Fig. 2, e.) 
' Nervure. A strong vein which, starting from the attachment of the wing of 
the male, runs along the anterior edge of the wing,.a little within it: at 
about half its length a branch runs obliquely towards the posterior edge. 
(Plate 1., 16; Plate xix.,f; Plate xxi.) 
Normal. According to rule—not exceptional. 
Ocelli. Two, four, or six minute circular simple organs, on the head of the 
male: probably organs of vision. In the Monophlebide they would seem 
* Report of the Entomologist, U.S. Dep, of Agric. 1880, p. 277, note. 
