202 MR. A. MURRAY'S MONOGRAPH OF THE FAMILY OF NITIDULARLE. 
(Subgenus COLASTUS proper.) 
Caput modicum. Maribus thorax haud dilatatus et tibiae antice haud ditatus 
The thorax is not dilated nor are the anterior tibie distorted in the males in this 
subgenus. It may be partitioned into several groups, thus :— 
SECTION I. Broad and convex*. Texture not soft nor shagreened. Type, C. latus (Pl. XXXIV. fig. 2). 
II. Moderately broad and convex. Texture soft. Type, C. pubescens. 
III. Moderately broad, much depressed, with the thorax as if a roller had passed over it. 
Type, C. amputatus (Pl. XXXIV. fig. 3) and C. signaticollis (woodcut, fig. 42). 
IV. Elongate. 
a. Texture not soft, dull, nor shagreened. Type, C. decorus. 
B. Texture dull and shagreened. Type, C. unicolor (Pl. XXXIV. fig. 4). 
y. Texture soft, dull, not shagreened. Type, C. infimus. 
Section I. Broad and convex. Texture not soft nor shagreened. 
a. Colour of the body below red. Thorax red, or mostly red. 
8. COLASTUS FERVIDUS. 
Subnitidus, sparsim punctatus, totus lete rufus, pube fulva vestitus; elytris seriatim 
punetatis et pubescentibus. Long. 2 lin., lat. 1} lin. 
Habitat apud flumina Amazonum. 
Entirely of a bright testaceous red colour, shining, clothed with a somewhat long ful- 
vous pubescence. Head rather coarsely punctate. Thorax more sparingly punctate, short, 
broad, base strongly bisinuate; posterior angles acute, projecting backwards ; anterior 
angles rounded; sides rounded. Scutellum large, slightly punctate. Elytra punctate and 
pubescent in rows. Abdominal segments more finely punctate. 
From Villa Nova on the Amazons. There is a single specimen in the British Museum. 
9. COLASTUS HEYDENI. 
C. fervido valde affinis, forsan varietas ejus; nitidus, læte rufus, fulvo pubescens ; capite, 
thorace antice lineis tribus longitudinalibus radiatim divergentibus et pygidio macula 
centrali nigro-piceis. Long. 2 lin., lat. 14 lin. 
Habitat in Brasilia. 
Closely allied to C. fervidus; perhaps only a variety. It is of a bright testaceous red 
eolour, but has the head, three longitudinal stripes like rays diverging backwards from 
the anterior part of the thorax, and a longitudinal patch on the middle of the pygidium 
pitchy black. The thorax is not quite so convex as in C. fervidus, but there is little 
other distinction between them. 
From Rio Janeiro. Named in honour of Herr von Heyden, of Trankfort-on-Maine, 
the study of whose large collection has furnished me with much valuable information. 
I have seen only a single specimen, which is in the collection of Professor Boheman. 
* Of course the word ‘convex’ is used merely in a comparative sense. It is inapplicable in a literal sense in a genus 
few of whose members are more convex than a thread-paper. 
