248 Annals Entomological Society of America [Vol. V, 
viewed from the cephalic aspect, are on the ventro-lateral 
regions of the head. 
Antenne.—Mesad and slightly ventrad of the ocelli are 
located the three-segmented antennz (at). Each consists of a 
conical-shaped basal segment bearing on its distal end two 
similar, cylindrical segments. On the distal end of the third 
segment, two unequal sete are borne, the mesal one being 
the longer. 
Front.—The triangular area included within the arms of 
the Y, is the front (/). 
Clypeus.—The clypeus (cl) is attached to the ventral edge 
of the front and forms a transverse bar, bearing a single seta 
on each lateral end. 
Labrum.—At the apex of the clypeus, there is borne a 
bilobed area (/r), which has on its ventral edge a deep notch, 
which makes the labrum bilobed. On the lateral and ventral 
parts of these lobes are borne seta. Three large setz for each 
lobe seems to be the constant number in the various specimens 
examined, while there is a’ variation in the number of small 
setae on the depressed region above the notch. 
Mandibles.—The two stout mandibles (md) meet in a zigzag 
line caudad of the labrum. The zigzag line is due to the inter- 
locking of the four dark, tooth-like projections which occur on 
the mesal edge of the laterally opening mandibles. The man- 
dibles are connected to the head proper at the lateral margins 
of the labrum and maxille. Each mandible bears on its distal 
median portion a single seta. 
Maxille.—Directly caudad of the proximal portion of the 
mandibles are two globular maxilla (mx), each of which bears 
ventrally a three-segmented, tapering palpus. The distal seg- 
ment of the palpus is very small. 
Labium.—Mesad of the two maxille, there is a wedge- 
shaped labium (/b), which gives rise to a tubular projection at 
its caudo-distal edge. 
Spinneret.—This tubular projection (2), which extends 
caudad and ventrad, is the spinneret, from which the silk 
is exuded. 
THORAX.—The thorax, being the second region of the body, 
is adjacent to the head and consists of three segments as follows: 
Prothorax (Fig. 1).—The prothorax is the cephalic segment 
of the thorax and is comparatively smooth and not transversely 
