26 
periphery. These are large, occupying full two-thirds of the entire 
head. They are of a deep black color, and are separated from each 
other on the top of the head only by a slight and almost impercep- 
tible cleft, so that when viewed in front they appear like a continu- 
ous broad black band surrounding the head, and interrupted only 
below at the mouth, thus resembling a horseshoe in their figure. 
The face is pale yellow. In its centre, and contiguous to each other, 
are two pale yellow tubercles or spherical eminences, more or less 
conspicuous, on which the antenne are inserted, and which are by 
some regarded as forming a joint of these organs, in additiow to the 
number commonly stated. The antenne are of a deep brown or 
black color, less intense than the eyes. They are of about the same 
length as the body, and composed of twelve joints. Each joint 
(Plate 5, fig. e) is commonly oblong, with a marked contraction in 
its middle, a shape whichis sometimes designated as ‘ coarctiform,’ 
and is surrounded with a whirl or row of hairs near its base, and 
another near its apex.* The joints are ordinarily about thrice as 
long as they are broad, their diameter being but little less than that 
of the legs. They are connected together by a slender thread inter- 
vening between each joint, and about a fourth as long as the joints 
themselves. The two palpi are pale yellow, and clothed with shortish 
hairs : each is composed of four oval joints ; the terminal one being 
longer, but of the same diameter with the preceding. 
The THorax is of a pale yellow color ; its upper side commonly 
tinged with fulvous brown, which sometimes, though rarely, forms 
three vitte or longitudinal spots forward of the middle. It is of an 
ovate form, its greatest breadth being immediately back of the wing 
sockets. Its vertical diameter much exceeds the transverse, as is 
common in most species of Tipulidae, the breast jutting down far 
below the level of the head and abdomen. The poisers are oval, 
* Not unfrequently, however, singular anomalies occur in these joints. Thus in 
some the contraction will be so considerable as to cause the segment to appear like 
two globular joints slightly but distinctly separated from each other; whilst other seg- 
ments of the same series are abbreviated and dilated, the usual contraction thus be- 
coming obsolete, and the joint taking on a short cylindrical form. It would thusseem 
as though we, in the female, met with the twenty-four joints of the male antenna in 
a modified or imperfectly developed condition ; that what appears as a single oblong 
coarctiform joint, is in reality two joints united, This would give but a single whirl 
of hairs to each joint, as is common in most of the species of this genus. 
