127 
This insect is intermediate in size between the Ad. punctulatus 
and Ad. angustatus, and is readily distinguished from either of the 
species here described by its denuded appearance; the scales and 
hairs, which are sparingly scattered over the body, only become visi- 
ble with the assistance of a moderately strong lens. 
The rostrum is about twice as long as the head, very thickly 
though finely punctured, and the punctures are confluent; in the 
middle is a distinct carina. The head is separated from the rostrum 
by a transverse and somewhat shallow depression, and in the middle 
of this depression is a small fovea: the upper surface of the head, 
as well as the thorax, is very thickly and finely punctured, and the 
punctures are confluent. The thorax is rather broader than long, 
subcylindrical, truncated before and behind; the upper surface is 
slightly convex, and the sides are somewhat rounded, being slightly 
dilated a little in front of the middle. The elytra are of an elongate- 
oval form, moderately convex, somewhat attenuated at the apex, 
but with that part rounded; they are distinctly punctate-striated ; 
the punctures are arranged closely together, and the interstices of 
the striz are narrow, slightly convex, and very delicately punctured. 
Cylydrorhinus dngulatus.—Under this name M. Guerin-Meneville 
describes, in the ‘ Revue Zoologique’ (No. 7, 1841, p. 217), a species 
of Curculio, from Port Famine, which I am inclined to regard as 
specifically identical with specimens brought by Mr. Darwin from 
St. Cruz and St. Julian. 
M. Guerin states that the elytra are covered above with large 
deep punctures arranged in longitudinal strie, at the base of each 
of which is a very small tubercle, and which are united together by 
an indistinct transverse impression. 
In the specimens brought by Mr. Darwin, the elytra are deeply 
punctate-striate at the base, but from the base towards the apex the 
punctures gradually decrease in size; the minute tubercles are situ- 
ated on the anterior margin of each puncture, and in addition to the 
strie of punctures, the elytra are for the most part covered with 
somewhat irregular transverse rugz; these are most distinct on the 
sides of the elytra (or rather what appears to be the side, for the 
elytra are strongly keeled at some little distance from the lateral 
margin, so that that part is hidden as we view the insect from above), 
less distinct on the apical portion, and do not extend to the disc. 
The apical portion of each elytron is slightly produced, and the 
elytra appear as it were terminated by a tubercle; near the apex, 
on each side, is another tubercle. The thorax has a distinct fovea 
on each side, in the middle and near the lateral margin. The size 
of the specimens from Port St. Cruz varies from length 9} lin., width 
44 lin., to length 72 lin., width 32 lin. 
_ A specimen from St. Julian differs in being considerably smaller 
and more deeply sculptured, and in having a small patch of white 
scales near the apex of the elytra; the interstice between the fourth 
and fifth striz is somewhat raised. Length 7 lines. 
In the collection is a specimen, without label, which agrees with 
this variety, as I presume it is. Length 6} lines. 
