220 Mr. R. I. Pocock on 



Measurements in millimetres. — Total length 24 ; length of 

 carapace 10, of palp 27, of first leg 41, second 37, third 35, 

 fourth 44. 



Loc. El Kubar. 



Up to the present time the genus Monocentropus was re- 

 presented bj a sing-le species, M. Balfouri, Poc. known only 

 from Sokotra. The discovery of the genus in Arabia is 

 most interesting. The Arabian species is much smaller than 

 the Sokotran, has uniformly coloured legs and exceptionally 

 long palpi. 



XXV. — Descriptions of Four neio Arachnida of the Orders 

 Pedipalpi, Solifuga^, and ArancK. By R. I. PocoCK. 



1. A NEW Species of Pedipalp of the Genus 

 Heteeophstnus. 



Genus Heteropheynus, Poc. 



Since writing the descriptions of the two new species of 

 Heterophryjius which appeared in the ' Annals ' for March 

 of last year, a fresh consignment of material from S. America 

 lias brought two additional specimens of U. armiger, one 

 from Butim in N. Ecuador, the other from the River Durango, 

 N.W. Ecuador. Both of these substantiate the constancy of 

 the characters upon which the species was based, one of the 

 specimens being peculiarly interesting in this connection 

 on account of its immaturity. In addition to these, another 

 well-marked species of the genus was received from Peru. 

 This I propose to diagnose and describe as follows : — 



Heterophrynus elaphus, sp. n. 



Colour of carapace and chelje deep reddish brown; legs 

 paler yellowish red, without annulations. 



Carapace, chelce, and femora less coarsely granular, outer 

 and upper side of " hand " smooth, except for a few granules 

 at its proximal end on the outer side; chelae short, shorter 

 than iu any known species except H. alces, the femur much 

 shorter than the width of the carapace, the tibia as long as 

 its width, femora of legs about twice the width. All the 

 spines on the chelce long ; femur armed with five spines as in 

 /J. cervinus, armiger^ and alces, and with four below as in 

 cervinus, and progressively decreasing in length from the 



