250 On a new Species of Liphistius. 
circumstances, the conclusion seems inevitable that the ex- 
ample possessing the four mammillary organs (and these 
placed in so abnormal a position), whatever may be their 
true nature and office, must be of a different species from 
that described by Prof. Schiédte. 
I therefore propose to call the British-Museum example 
Liphistius mammillanus, 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 L. desultor (Schiddte), 
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. 1,666); and immediately 
behind them are four mammillary organs, placed two and two, 
as represented (fig.1,aaaa); the two 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 
Fig. 1. Fig. 2. Fig. 3. 
ZV \i4 Np po 
Vaan Vay (Gane 1A 
Fee po aa 
C2 Ro ie 
YY n yn A 
Fig. 1. Underside of abdomen: a@aaa,mammillary organs; bb 6b, spi- 
racular plates; c, anal tubercle and orifice. Fg. 2. a, sternum; 
b, labium. F%g. 5. 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. Schiddte’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. 1, c). ; 
The sternum (fig. 2,a) differs a little m form from that of 
Liphistius desultor ; while the eyes appear to be similar both 
