24 . MALACODERMATA. 
At first sight this is very similar to P. letowrnewri. The following points of dif- 
ference indicate, I believe, specific rank:—The thorax is shorter and has a less even 
surface ; it is not so evenly rounded in front; the head is reddish between the eyes; 
and the antenne are longer; the scutellum is red, and the suture itself not black at 
the base; but there is a short black streak on each side of it from the scutellum; the 
elytra are more convex, and their alternate interstices not raised, excepting the humeral 
and discoidal ones at the base. In some specimens the thorax exhibits transverse 
oblique rugosities, one of which forms a sulcus united with the channel of the disk 
near the base. 
17. Plateros rubricatus. 
Ochraceo-rufus, antennis, palpis, abdomine pedibusque (basi excepta) nigris, elytris interstitiis alternis eleva- 
tioribus. Long. 10 millim. 
Hab. Guatemata, Chacoj, La Tinta, Pancina (Champion). 
This species is also a very close ally of P. letowrneuri, and is, indeed, still nearer to it 
in form than is P. ochraceus. It is, however, clearly a distinct species. The head, 
thorax, and scutellum are entirely of the brick-red colour of the thorax ; and the whole 
of the sterna, with the coxe, trochanters, base of the femora, and even the first 
segment of the abdomen are also red. The thorax, moreover, is not so even as in 
letourneuri; it exhibits six depressions in addition to the basal channel—two on each 
side, and one on each side of the channel, somewhat suggesting an approach to a 
true Lros. 
18. Plateros mexicanus. 
Nigro-fumosus, prothoracis margine laterali et frontali elytrorumque humeris ochraceo-rubris vel roseis ; 
elytris punctato-striatis, interstitiis alternis elevatioribus. Long. 63-8 millim. ¢ 9. 
Hab. Mexico, Cordova (Sallé, Hoge). 
This species belongs to the first division of the genus, in which the elytra are 
moderately widened behind. ‘The only species yet described which it resembles 
is P. bourgeoisi.. It is scarcely more than half the size of that species; the elytra are 
not so black, and the red portions are more nearly pink; the disk is black, but never 
reaching the front margin, nor is there any central red line. The thoracic channel is 
open behind, and the base elevated, but not strongly in the middle. The antenne are 
more pubescent than in P. bourgeoisi; and the head is sometimes reddish above the 
mandibles, which are red. 
19. Plateros roseicollis. 
Niger, prothorace elytrorumque humeris tenuiter roseis, his interstitiis alternis modice elevatis. Long. 8-10 
millim. ¢. 
Hab. Mexico, Jacale (Sallé). 
