Scorpions from Central and South America. 389 



Centrums ruhricauda, sp. n. 



? . — Colour almost a uniform reddish black all over ; the 

 hands redder than the rest of the cheljB ; tarsi and pectines 

 yellow ; tail reddish ochre-brown. Granular crests on hand 

 evident and finely granular; crests on tail rather coarsely 

 granular, but the granules few in number and more spaced 

 than in allied forms ; on the iufero-lateral keel of the third 

 segment, for example, the granules are fewer than twenty 

 (15-19); vesicle granular; the spine not close up to the 

 aculeus. Sterna 2-4 smooth, punctured, especially number 3. 



Pectinal teeth 20—21. 



^. — Differing from the female in the normal sexual 

 features, but in addition with the legs bright yellow ; crests 

 on hand scarcely perceptible ; crest on tail weakly and 

 sparsely granular as in female ; vesicle parallel-sided when 

 viewed from below, bulging on each side at right angles at 

 the base of the aculeus. 



Pectinal teeth 21-23. 



Measurements in millimetres. — $ . Total length 80 ; length 

 of carapace 8"5, of tail 51. ^. Total length 103; length of 

 carapace 9, of tail 71. 



Loc. Managua in Costa Rica {^Dr. Rothschuh). Four 

 male and four female specimens. 



Centrums nigrescens^ sp. n. 



? . — Colour a uniform blackish green ; tarsi and distal half 

 of fingers ferruginous ; pectines fiavous ; coxfe and sternal 

 areas mesially ochraceous. Coarsely and thickly granular ; 

 middle finger-keel or hand strong, all the crests on the tail 

 strongly granular ; vesicle weakly granular ; the spine close 

 up to the base of the vesicle. 



Pectinal teeth 25-27. 



(J . — Like female in colour. Inferior crests on fifth caudal 

 segment distinct and granular ; vesicle about twice as long 

 as wide, almost smooth, its shoulders not very strongly ex- 

 panded. 



Pectinal teeth 28-30. 



3Ieasurements in millimetres. — ? . Total length 89, of 

 carapace 9, of tail 53*5. ^ . Total length 105, carapace 9, 

 tail 73. 



Loc. Xantipu (5500 feet alt.) (type) ; also Amula and 

 Orizaba. 



In colouring the female of this species resembles that of 

 rubricauda, except that the reddish tint upon the palpi and 



