" YY2 
Four somewhat interrupted and irregular striz run parallel with and 
near the suture, and there are two abbreviated oblique striz near the 
scutellum. Besides the ordinary ruge of the elytra, there are more 
marked ruge, which, though very irregular, have a tendency to a 
transverse disposition, and these cover the outer half of each elytron. 
The prothorax is punctured beneath and rugose between the legs, as 
well as the mesosternum and metasternum. ‘The three basal seg- 
ments of the abdomen are covered with fine but distinct rugz, and 
though these rugz, for the most part, have a longitudinal direction, 
they are much more irregular than in most species of the genus. 
The two terminal segments are punctured, but in the penultimate 
segment the punctures are very few in number, and confined to the 
sides. The spines at the apex of the anterior tibize are more slender 
and proportionately longer than in N. /evis. 
Besides the two specimens, one from Bahia Blanca and the other 
rather further south (San Blas), Mr. Darwin’s collection contains a 
specimen from Tierra del Fuego which is smaller (length 62 lin., 
width 32 lines) and proportionately narrower; but these differences 
are combined with a greater length of tarsus, and are precisely such 
differences as exist between the sexes of other species; in fact, it is 
no doubt the male of the insect from which the above description is 
taken. 
Nycrevia Westwooprt. Nyct. brevitér ovata, nitida, atra ; capite 
subpunctato ; thorace transverso, postice pauld latiore quam antice, 
leviter convexo, levi, margine laterali imperspicue crenulato ; ely- 
tris ovatis, profunde striatis, interstitiis convewis, striis utrinque 
_ad suturam duabus longitudinalibus, striis reliquis obliquis. 
Long. corp. 74 lin. ; lat. 43 lin. 
Hab. Port Desire. 
Head with a few punctures in front. Thorax convex, about twice 
as broad as long, with the middle and hinder parts about equal in 
width, and the fore-part contracted; the anterior part emarginated, 
the emarginated portion in the form of a segment of a circle; the 
hinder margin but slightly waved; a distinct groove runs close to 
the anterior and lateral margins, which latter are crenulated. Elytra 
short and rounded ; the length and width equal, if the produced apical 
portion be omitted in the measurement; the apex is moderately 
produced : the whole surface of the elytra is covered with deep strie, 
leaving convex interspaces which are scarcely broader than the 
grooves; on each side of, and parallel with the suture, are two of 
these striz; the remaining grooves are oblique, and for the most 
part converge towards the apical portion of the elytra: on the sides 
of the elytra, and more especially towards the apex, the grooves have 
a tendency to a transverse disposition. The mentum is very coarsely 
punctured, and there are some distinct punctures on the sides of the 
head beneath. The prothorax presents a few large scattered punc- 
tures beneath, some short irregular (but for the most part transverse) 
ruge at the lateral margin, and some longitudinal ruge near the base 
of the legs; between the legs the prosternum has some confluent 
