Mr. R. I. Pocock on Neotropical Scorpions. 87 
Chactas levipes (Karsch). 
Chactas levipes, Karsch, Mitth. Munch. ent. Ver. 1879, p. 131. 
The species that Dr. Karsch described as Broteas levipes is 
a Chactas. The British Museum has a single male example 
of it. 
Chactas cequinoctialis (Karsch). 
Chactas equinoctialis, Karsch, t. c. p. 180. 
This species, described as a Broteas, is also a Chactas. 
The Museum has a male example from Porto Cabello. 
Chactas Keyserlingti, sp. n. 
Colour pitch-black ; legs, lower surface, and vesicle just 
tinted with ferruginous. 
Curapace smooth and polished above, distinctly granular 
at the sides, the anterior border evidently emarginate and the 
longitudinal furrow deep, as long as the first and second 
caudal segments and one third of the third; distance between 
the median eyes rather greater than a diameter, that between 
the lateral about equal to a diameter. 
The ¢ergites smooth and polished, the last smooth only in 
front and in the middle of its upper surface, the rest being 
distinctly granular. 
Sternites entirely smooth and punctured. 
Tail weak, about three and three quarter times as long as 
the carapace, narrowed posteriorly, the second segment as 
long as wide ; the upper surface of the segments smooth and 
sulcate in the middle, conspicuously granular (subserially on 
the fourth) at the sides, the superior and supero-lateral keels 
present and distinctly granular, as is the interval between 
them; the lower surface of these segments smooth and 
polished, the fourth only obsoletely keeled at the sides; the 
fifth segment more than twice as long as wide; its upper 
surface sulcate in front, flat behind, and in front distinctly 
granular at the sides, the edges rounded, granular, the lateral 
and lower surfaces also granular, the median lateral keel 
present only in front; the infero-lateral and median keels 
distinct and granular ; vesicle serially granular below and at 
the sides and very sparsely so above, flat and sulcate above, 
as wide as the fifth segment. 
Palpi elongate ; the humerus and brachium granular and 
carinate, the latter with one or two small denticles above and 
below at the base of its anterior surface ; manus long and 
slender, not twice as wide as the brachium, its width a little 
