440 T'ransactions 
much shortened in height to receive the genitalia. The female abdomen 
ends in a pair of stylets, and when the apical segments are extruded they 
appear as shown in fig. 3. In some species the membrane of the third 
abdominal segment of the female on each side may be inflated to form a 
bilobed bladder (fig. 4), the membrane when not inflated forming a whitish 
wrinkled patch. These peculiar bladders have apparently to do with the 
aquatic habits of the species, since Mr. J. W. Campbell, who found the 
specimens, states that the flies (Hilara flavinceris n. sp.) were found 
beneath an overhanging rock above a stream 
The vestiture consists of bristles and hairs, the former arranged in 
definite systems which are beyond doubt of considerable taxonomic value, 
and in one or two genera a supplementary synopsis of the species has been 
drawn up, based on the thoracic and occipital chaetotaxy of the males. 
delicate frontal ones; the first and second antennal joints are bristly or 
haired, and in some forms there are bristles or hairs on the face; the 
palpi are bristly or haired. On the dorsum of the thorax the bristles are 
either well developed or delicate and small, the acrostichals and dorso- 
centrals frequently being represented by one or more rows of small 
bristles which usually lengthen posteriorly, the dorsocentrals often ending 
in a pair of well-developed bristles. The bristles on the prothorax show 
that certain species are semi-aquatic, since a species of H emerodromia has 
been found in the mud of a stream (Lundbeck). 
The writer, while dissecting the abdomen of the female of Hilara 
flavinceris n. sp., found the ovaries filled with yellowish-brown eggs, €a€ 
of which is oval with one end truncated and surrounded by a narrow 11 
(fig. 5); this end is covered by a whitish granular membrane from v 
middle of which is the micropilar projection (fig. 6); the surface of Ms 
egg is sculptured by hexagonal depressions, 
