I9I3-] I- ^- Henderson : Arachnida, I. 131 



tail. The black mottling on the sterna of the new species is 

 characteristic. Other differences, as for example in the characters 

 of the vesicle, exist between the two species. 



4. Chaerilus tricostatus, Pocock. 



C. tricostatus, Pocock, Journ. Bomb. N. H. Soc, vol. xii, p. 266 

 (1899); Fauna of India, Arachnida, p. 59 (1900). 



Habitat. — Four specimens (all 2 ) from the Abor country : — 



(i) Rotung, 1300 ft., under stones, 21-xii-ii {5. TF. Kemp). 



(2) Rotung, 1300 ft., 24-xii-ii (F. H. Stewart). 



{3) Rotung, 1300 ft., 29-xii-ii (M. de Courcy). 



(4) Upper Rotung, 2000 ft., 22-i-i2 (5. W. Kemp). 



This species was described from two dried specimens (both cf ) 

 in the collection of the British Museum, from Sadiya, Assam, a 

 locality close to the border of the Abor country. A comparison 

 of the two sets of specimens reveals no difference of any importance, 

 except in the proportions of the joints of the chelae and these are 

 no doubt sexual characters. The Abor specimens have a more 

 strongly granulated carapace than those from Sadiya and it may be 



Fig. 2. — Hand of Chcerilus tricostatus, Pocock, $ , nat. size. 



that they belong to a local race of C. tricostatus, but this question 

 may be deferred till more material is forthcoming. As the female 

 was formerly unknown I take this opportunity of describing it. 



Colour. — Upper surface black; ventral surface also black, 

 with the exception of the cephalothorax which is mottled with 

 brown and yellow. Pectinal teeth yellow. Tarsi 3^ellowish. Man- 

 dibles pale brown. V'esicle reddish brown. 



Carapace somewhat uniformly granulated, the granules best 

 developed on the more elevated parts. Carapace longer than the 

 first and second caudal segments, about equal to the third and 

 'fourth, longer than the fifth segment. 



Terga granular throughout, with a series of larger granules on 

 the posterior border, two of which form well-marked black pearl^^ 

 tubercles The latter are best developed on the third, fourth, fifth 

 and sixth terga, and on the last three of these have one or two 

 enlarged granules in front, arranged in short antero-posteri or lines 

 with the tubercles. 



Sterna smooth, the last with four ill-defined crests formed by 

 granules. An oval yellow patch occurs near the posterior margin 

 of the third sternum. 



