152 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 95 
the male and a figure of the genitalia it will be difficult to separate 
the other races from it, although the shape of the head and measure- 
ments given will be of considerable assistance. 
The male of zneapectata is superficially very close to that of H. 
mandibularis, both being more or less of the same size, shape, sexual 
dimorphism, and markings and both with the same type of scent gland 
on the fifth abdominal pleurite. However, it may be separated from 
all races of mandibularis by the following characters: 
The endomeral plate lacks the lateral prongs at its distal end, and 
the sac that lies between them, these being replaced by a bifurcated 
projection in the median portion of the transverse, posterior margin, 
or else a single median projection of varying shape, which may be 
the penis. A second character present in al/ males of ineapectata 
I have seen is the arrangement of the short, heavy spines on the 
dorsal surface of the abdomen. There is a spine just znside the 
inner edge of pleurite IV, near its posterior margin; a second spine 
is just outside the inner edge of pleurite III, also near its posterior 
margin, while a third spine is on the posterior margin of the second 
tergite, some distance inside the pleurite, so that the three spines are 
almost on a diagonal line with each other. (Note arrangement of 
spines under description of H. mandibularis and H. temporalis.) 
The females of inexpecata are very similar to those of H. mandi- 
bularis and H. temporalis, except in two characters, by which each of 
the three may be easily distinguished, viz: the shape of abdominal seg- 
ment VII and the chaetotaxy of the pleural plates of the abdomen. 
In tnexpectata abdominal segment VII protrudes but slightly beyond 
VI, is almost transverse on its posterior margin (only a slight rounded 
median projection), but also has a narrow, elongated, median emargi- 
nation, the entrance to which is practically closed. There are four 
abdominal spines, all on the posterior margin of the tergal plates of 
segments II to V, the one on V being at the inner edge of the pleurite, 
with each succeeding spine set farther inward, toward the center of 
the abdomen, so the four spines form diagonal lines across the abdomen 
converging toward the thorax. 
There are minor characters for separating the races of each species, 
such as size and proportion of the various body segments, but there 
are cases where the females of the different races are very difficult 
to differentiate, and then only by careful measurements and compari- 
son with actual specimens. The figures given will serve better for 
distinguishing these differences between closely allied forms than 
pages of lengthy description. 
