492 Mr. R. I. Pocock on some 



equal, and by the fourth leg exceeding the first by more than 

 its tarsus in length instead of by less than its tarsus. 



The only species of this group previously recorded from 

 St. Thomas is that described by Karsch as Selenocosmia 

 Greeffi, the generic position of which is still a little doubtful. 

 In his original description (SB. Ges. Naturwiss. Marburg, 

 1884, p. 60) Karsch writes, when describing the legs, " Die 

 Metatarsen der beiden Hinterpaare an der Spitze unterhalb 

 mit . . . Scopula"; whereas subsequently (Berl. ent. Zeit. 

 1886, p. 83) he says lt Scopula an Metatarsus iv. fast hart bis 

 zur Basis des Gliedes reichend." These statements clearly 

 involve either an error of identification, the author con- 

 founding two distinct genera as one species, or of observation. 

 Simon has assumed the latter to be the case, and, following 

 him, I have on the strength of the assumption referred 

 S. Greeffi to the genus Hysterocrates. If, however, as is 

 possible, the specimens that Karsch first described as 

 8. Greeffi have the scopula on the fourth protarsus confined 

 to the apex of the segment the species will fall no doubt into 

 Phoneyusa. 



Assuming that it falls into Hysterocrates, the known species 

 from the island of St. Thomas may be tabulated as follows : — 



a. Legs short ; first leg just exceeding twice the length of 



the carapace (62 : 30) ; fourth leg only twice and one 



sixth the length of the carapace (according to Karsch). Greeffi. 



b. Legs longer; first leg* not less than twice and one 



third the length of the carapace ; fourth leg not less 

 than twice and two thirds the length of the carapace. 

 a 1 . Tarsus of palp swollen at base, wider and higher 



than tibia didymus. 



b\ Tarsus of palp normally cylindrical, not wider than 

 tibia. 

 a 2 . Fourth leg not thickened ; carapace a little longer 



than its patella and tibia or protarsus and tarsus . . scepticus. 

 b 2 . Fourth leg a little thickened ; carapace con- 

 siderably shorter than its patella and tibia and 

 protarsus and tarsus apostolicus. 



ClTHAEISCHIUS, gen. nov. 



Resembling Phoneyusa, Karsch (with which, pending a 

 re-examination of the types, I provisionally include Harpaxo- 

 theria, Sim., and Pelinobius, Karsch), in the restriction of the 



* The legs are here measured from the base of the femur. Karsch's 

 measurements may contain a greater number of segments, but cannot 

 contain a smaller. I have assumed that they contain the same. If they 

 contain a greater number of segments, the shortness of the legs in Greeffi 

 is even greater than here represented. 



