in the British Museum. 135 



? . — A much darker specimen from Upper Richmond 

 Valley is probably a female ; as the following dimensions 

 make evident, neither the absolute nor the relative propor- 

 tions are quite alike ; but in all other respects it seems to 

 be similar to the above-described male, which is perhaps a 

 young one. 



Cephalothorax 0-588 (0 532) ; abdomen 1-260 (0700) mm. 



Palps : trochantin 0-280 (0-168) ; femur 0-564 (0-210) ; 

 tibia 0-476 (0-252) ; hand O'oOO (0-392) ; finger 0-418 mm. 



Material, ^c. — This species seems to be very common in 

 the West Indies. I have examined specimens from several 

 localities at St. Vincent, collected partly by Mons. E. Simon 

 and partly by ^Iv. H. H. Smith ; the latter seems to have 

 taken most of his specimens under rubbish or rotten leaves 

 in mountainous forests (1200-3000 feet) during the months 

 from January to March. 



Remarks. — This species seems to be nearly related to 

 Id. crassimanum, Bal. (ii, p. 542), from which it differs in 

 the following chara -ters : — The aladominal sclerites seem to 

 he smooth, not granular; the epistoma is rounded, not sub- 

 conical ; the immovable finger of the palp has three, not two, 

 tactile hairs ; the hand is not 1*7 times longer and not 1*3 

 times broader than fingers are long, but longer than hand 

 is broad. 



II.— CoxAL Sac. (PI. VII. figs. 4 b-f.) 



If we carefully examine the fourth pair of coxae in the 

 male of Chelifer socotrensis, sp. n., we shall find a remarkable 

 organ which I propose to call the coxal sac. This organ is 

 only slightly developed in this species compared with many 

 othei's more or less nearly related to Ch. cancroides, L., for 

 instance, Ch. sculpturatus, Lewis (p. 121) ; in this paper I 

 shall give only the description of its structure in Ch. soco- 

 trensis. My investigations on its modifications and fuller 

 development in other forms 1 hope to get finished in a not 

 too distant future. The cox-al sac is situated in the inner 

 and hinder part of the coxae, and directed towards the postero- 

 interior corner (PI. VII. fig. 4/>j, where [irobably an opening 

 is found through which the hairs of the funnel are directed. 

 The sac, which is rounded and elongated, consists of two 

 portions which are well marked otf from each other 

 dorsally and laterally. I was not able to settle the question 

 whether the sides which I have called dorsal and ventral 

 really are so or not. 1 use these terms because the position 

 of this or^au iu one of the specimens I examined seems to 



