148 Mr. H. W. Bates on the Longicorn Coleoptera 



crested with hairs, the rest of the surface being free from in- 

 equalities. The terminal abdominal segment is of normal size 

 and obtuse in both sexes, the female not having an exserted 

 ovipositor. The sterna, head, and muzzle are of the same shape 

 and structure as in the majority of the Leiopodinse ; but the 

 eyes are rather smaller and more pointed beneath than in many 

 of the foregoing genera ; they resemble, however, very closely 

 the same organs in the restricted genus Leiopus. 



1. Cosmotoma rubella, u. sp. 



C. rufescens : thoracis lateribus obscurioribus : elytris tomento 

 argenteo strigosis, postice nigro fasciatis. Long. 2|-3|- lin. (6 

 exempl.) 



Head dull red. Antennae red, the hairy clothing black. 

 Thorax dull red, the sides behind tinged with dusky, and the 

 under surface black. Elytra dull red, streaked with silvery 

 tomentum ; behind the middle is a broad black fascia, folfowed 

 by a narrow silvery belt, the apex itself being dusky. Body 

 beneath dusky, with patches of grey pile. Legs reddish testa- 

 ceous. 



A common insect on broken branches in the forest at Para 

 and on the banks of the Tapajos. I have received Cayenne 

 specimens from Paris as Cosmotoma venustulum of Dejean's Cata- 

 logue; but, according to Chevrolat (Journal of Entomology, 

 vol. i. p. 188), the C. venustulum of Dejean's Catalogue is the 

 species described by M. Thomson as Beltista adjuncta, which, 

 from the description given, cannot be the same as our C. 

 rubella. 



2. Cosmotoma nigricollis, n. sp. 



C. rufescens : thorace nigro velutino : elytris tomento argenteo 

 strigosis, postice nigro fasciatis. Long. 3f-4 lin. (5 exempl.) 



Head dull black. Antennae red, the hairy clothing black. 

 Thorax deep velvety black. Elytra dull red, streaked with 

 silvery tomentum ; behind the middle is a broad black fascia, 

 followed by a narrow silvery belt, the apex itself being dusky. 

 Body beneath dusky, with patches of grey pile. Legs reddish 

 testaceous. 



This form represents C. rubella on the Upper Amazons, being 

 as common an insect at Ega as its sister form is at Para. It is 

 possible that it may be the species described by Thomson as 

 Beltista adjuncta; but the following phrase in this author's 

 diagnosis, "prothorax et elytra extremitate nigra, illo versus 

 apicem maculis 2 albis nebulosis," is quite unsuited to our C. 

 nigricollis, there being no white spots near the apex of the tho- 

 rax. The locality of Beltista adjuncta is given as San Domingo; 



