MR. J. O. WESTWOOD ON NYCTERIBIA. 287 
tremity, especially at the sides ; and the abdomen is terminated by a distinct and con- 
siderably narrower segment, notched at the tip, as though formed of two united incras- 
sated styles, having moreover, as it were, a raised longitudinal lobe along its centre. 
On the under side the basal segment is, as usual, very distinct and ciliated ; then fol- 
lows a large and nearly square region, (corresponding with the superior pilose portion,) 
having three transverse series of hairs, of which the last is the most distinct : this is 
succeeded by a transverse region similarly terminated, which is again followed by a 
lunate and ciliated portion, and the last segment is channelled down the middle. This 
insect must be regarded as a female, (its specific identity with the former being unques- 
tionable,) notwithstanding that, from the existence and situation of the several trans- 
verse series of hairs, no less than seven segments are indicated on the under side. 
Two of the specimens of this species in the British Museum are males; the third is a 
female, and exhibits more strongly the curious trilobed structure of the terminal seg- 
ment of the abdomen. 
Mr. Stephens’s specimens of the species described by Montagu, and named Her- 
manni by Dr. Leach, are of one sex, and very differently constructed from any of the 
preceding insects ; and I regret that their dried and shrivelled state prevents my so 
completely ascertaining their structure as I could have wished. The basal segment of 
the abdomen is much produced above and at the sides, but it does not appear to me to 
overlap any of the following segments, two of which immediately succeed, and are very 
short ; the terminal fourth joint is large, semi-ovate, and from beneath its sides, at 
the extremity, arise two porrected styles, furnished at the tip with strong bristles. 
On the under side the basal segment is reduced to its ordinary and ciliated form and 
size; then follow two short segments corresponding with those on the upper side ; 
which are succeeded by a large segment corresponding with the terminal superior 
one ; and between the inferior margins of the latter and the extremity of the former is 
protruded a distinct and convex segment, having its upper margins armed with the two 
porrected styles above mentioned. I could not, however, distinguish any traces of a 
central lobe or style. 
This description accords with Dr. Leach’s characters of Nycteribia given above. Of 
Dr. Leach’s three specimens of this species in the British Museum, two (as well as the 
specimen received by him from Bonelli) are of the same styliferous sex as Mr. Stephens’s : 
but the other British specimen is, fortunately, of the opposite sex. It is, however, 
in too shrivelled a state to allow me to give a more minute description of its abdomen 
than that it is more robust than in the styliferous specimens, that its upper side exhibits 
four or five articulations, and that its extremity beneath is distinctly furnished with two 
incurved styles closely applied along the under surface of the terminal joint. These two 
organs, hitherto unnoticed by the describers of this species, thus clearly indicate the 
male sex, confirming the opinion of Dr. Leach, and proving that the female is organized, 
