174 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
OTOSTIGMUS SUITUS, sp. nov. 
Color olive-green with some of the dorsal plates appearing darker 
along the caudal margin. Antennae more brownish excepting at 
base. 
Head distinctly punctate. Marked in front of caudal margin with 
two short longitudinal furrows. 
Antennae seventeen jointed.! First two or two and a half articles 
glabrous (the third in type partially rubbed so that precise extent of 
glabrous condition is uncertain); other articles clothed densely with 
the usual short brown hairs. | 
Dorsal plates from the fourth, inclusive, caudad with two distinct 
median sulci; a longitudinal depression or furrow on each side, but 
true margination present only on the twenty-first plate, plates mostly 
depressed between median sulci and with a weakly developed median 
keel indicated on plates from the third caudad; the surface and edges 
of plates wholly smooth. Last dorsal plate with posterior margin 
bowed moderately caudad. A median pit-like depression in front of 
caudal margin and a keel in front of this as on the other plates. 
(Plate 3, fig. 4). 
Prosternum with 4+4 teeth of which the second from the mesal 
incision on each side is the largest, the third being next. 
Ventral plates without a trace of longitudinal sulci. Each with three 
distinct, pit-like, or more or less longitudinal, impressions arranged 
in a triangle with the apex cephalad, and with three short longitudinal 
impressions in a transverse row in front of the caudal margin. Last 
ventral plate strongly narrowed caudad. Truncate caudad with the 
corners a little rounded. Impressed with a distinct median longi- 
tudinal furrow. (Plate 3, fig. 3). 
Coxopleurae of last legs without any true process, being a little 
roundly extended caudad; without any spines. 
Length cir. 55 mm. 
Locality.— State of Matto Grosso: Madeira-Mamore R. R. camp 
41, on the Rio Madeira! (W. M. Mann). 
One specimen was secured. 
1On one side of type specimen there are but thirteen articles in the antenna, this 
being due, apparently, to breaking off of the antenna with subsequent regeneration 
of the distal article. 
