TAKKIIU: MiW liMil.AM) SAH('()I'IIA( ilDAK. O 
is protriuU'd wlu'ii tlu' Hy hn-aks its way out of tlir pupa case. The 
position of tlu' saf, as it lies retracted within the head of the achilt is 
indicated hy a series of (hishes. Hetweeii the \tiitral arms of the 
suture and the henfis in the eliitin marking' the hiteral limits of the 
facial plate are swollen ridj^e-like structures. These are the vibrissa! 
ridges or facialia (PI. 1, fig. 1, r.sr.). The area l)etween these and al)OVe 
the oral opening is the facial i)late (PI. 1, fig. !,//>.). According to 
Lowne, this consists of two lateral plates in the young iniag(t, which 
later become fused. Upon its upper part are borne the antennae 
(PI. 1, fig. 3). Below the base of the antennae, the upper three 
fourths of this plate is more heavily chitinized than the remainder and 
its lateral halves are slightly depressed with a scarcely discernible 
ridge between them. These lateral halves are the antennal fo\-eae 
(PI. 1, fig. 1, aiif.). The dividing ridge is very prominent in some 
Diptera and is called the carina or keel. 
The antennae depend from a weakly chitinized portion of the facial 
plate above the foveae. The articulation is quite firm and allows little 
movement. The first segment is comparatively small and partially 
concealed by the edge of the gena. It bears a few minute spines, 
visible just above the second segment. The latter is somewhat cone- 
shaped, smallest at the base, and is joined to the first by membrane 
which permits great freedom of movement. It is clothed with minute 
hairs and centrally on its anterior surface bears small, close set bristles, 
and near its distal end a single prominent one. The third segment is 
elongate, almost linear in outline, downy, and bears numerous organs 
of sense (PI. 1, fig. 4, ant. 3). Its inner surface is somewhat flattened, 
its outer slightly convex. An apparently almost immovable socket 
or joint unites it to the second. An irregular cone-like structure 
(PI. 1, figs. 2, 4) projects downward from the distal end of the second 
segment, and fits into a corresponding cavity in the base of the third. 
The former is covered with very small, reclinate, tooth-like projections; 
the latter is lined by similar proclinate structures. These interlock 
and little motion is permitted. On the proximal portion of the third 
segment just lateral to its anterior edge is the arista which (jonsists 
of three segments. The two first are very short and minutely bristly; 
the third is very long, slightly enlarged at its basal third, and plumose 
on its basal half. 
As previously stated all of the head capsule except the metacephalon 
and occipital sclerites, consists of a single plate. Other than the 
