250 



On a new Species of Liphistius. 



circumstances, the conclusion seems inevitable that the ex- 

 ample possessing tlic four mammillary or^^ans (and these 

 placed in so abnormal a position), whatever may be their 

 true nature and othce, must be of a different species from 

 that described by Prof. Schiodte. 



I therefore propose to call the British-Museum example 

 Lfp/iistius mammillanuSy and briefly to characterize it as 

 follows : — 



Liphistius mammillanus^ n. sp. 



Adult female, length 20 lines =42 millims. 



Abdomen similar in colour to that of Z. desidtor (Schiodte), 

 and its upperside similarly covered by a longitudinal series 

 of transverse articulated corneous plates. The spiracular plates 

 are four in number, grouped closely together beneath the fore 

 extremity of the abdomen (fig. 1, b b b b) ; and immediately 

 behind them are fom- mammillary organs, placed two and two, 

 as represented (fig. 1, a a a a) ; the tvvo foremost are much 

 larger than the two hinder ones, of a curved subconical or 

 rather tapering form, composed of several (about twelve) arti- 

 culations or rings, of which the basal one is much the largest ; 

 the two hinder organs are somewhat similar in form, though 

 much smaller, and the basal annulation is not nearly so broad 



Fiff. 2. 



^Cr^^i^ 



Fiff. 3. 



Fig. 1. Underside of abdomen : a a a a, mammillary organs ; bhbb, spi- 

 racular plates ; c, anal tubercle and orifice. Fiy. 2. a, sternum ; 

 b, labium. Fig. 3. One of the falces. 



in proportion ; the several annulations are fringed with short 

 hairs on their posterior edges. These organs are capable of 

 vertical, but not horizontal movement. The anal aperture 

 seems to be in rather a different position from that represented 

 in Prof. Schiodte's plate (fig. 7), where it occupies the posterior 

 extremity of the abdomen, while in the present spider it 

 is placed considerably beneath it (fig. l,c). 



The sternum (fig. 2, a) differs a little in form from that of 

 Liphistius desidtor ; while the eyes appear to be similar both 



