452 Mr. 1. W. Bates on the Longicorn Coleoptera 
Genus Gymnocerwus, Serv. 
Serville, Ann. Soc. Ent. Fr. 1835, p. 84. 
In this genus both sexes have eleven joints to the antenne. 
According to Serville, the ¢ has the terminal joint very long, 
Amongst the species which I propose to include in the genus, 
some have this joint as long as the tenth, others much shorter ; 
and it is always relatively shorter in the 9 thaninthe d, All 
the joints are naked; but the third in some species, and the 
fourth in others, are more or less thickened at the tip, The 
body is convex and rather broad, and the elytra somewhat more 
gradually rounded to the apex than in Anisocerus, 
This genus was omitted in Mr. White’s ‘Catalogue of the 
~ Longicorn Coleoptera of the British Museum ;’ and some of the 
species were included by him under Anisocerus, from which they 
are distinguishable by the naked antenne. 
1. Gymnocerus capucinus, White. 
Anisocerus capucinus, White, Ann. Nat. Hist. xvii. t.1.f.7; Cat, Long. 
Col. Brit. Mus. ii. p. 406. 
This remarkably beautiful species, which in its colours and 
markings resembles some kinds of Doryphora of the Chryso- 
melide group, I found only at Caripi, near Para. It occurred 
sparingly, in January, on dead branches of trees in the forest. 
The third antennal joint is considerably thickened at the apex. 
2. Gymnocerus dulcissimus, White, 
Anisocerus dulcissimus, White, Cat. Long. Col. Brit. Mus. ii. p. 406. 
I met with this species only on one occasion, in the forests on 
the banks of the Cupari, a branch of the Tapajos, in 4° S. lat. 
and 55 W. long. It is still more beautiful in colours than G. 
capucinus ; but I believe, with Mr. White, that it may be only a 
modification of that species. The third antennal joint is less 
thickened at its apex than in G. capucinus. 
Three individuals only occurred, on a decaying branch in the 
depths of the forest. 
3. Gymnocerus cratosomoides, n. sp. 
G. ovalis, convexus, tomentosus, ochraceo-fulvus: thorace levi: 
elytris seriatim punctato-granulatis, singulis prope basin tuberculo 
magno glabro instructis et apud medium breviter quadricarinatis, 
fascia lata undulata pone medium et marginibus posticis fuscis. 
Long. 93 lin. @. 
Head dull-greenish yellow, tomentose, smooth, Antenne slen- 
der, shining black, about the length of the body, the third joint 
scarcely thickened at the apex. Thorax about half the breadth 
of the elytra; lateral tubercles rather small, acute, the surface 
