1915. ] F. H. GRAVELY : Oriental Tarantulidae. 451 
Central Province : Nalanda, ca. goo-1000 ft.; Galagedara, ca. 
800-2000 ft.; Kandy, ca. 1500-2000 ft. ; 
Peradeniya, ca. 1800 ft. 
The sexes of this variety differ from one another in a more 
striking manner than do those either of the typical form or of the 
other variety of the species, and but for certain indications of an 
identical geographical distribution for the two and the fact that I 
have seen no female which superficially resembles the male of this 
variety ,and no male which resembles what I believe to be its female, 
it would hardly, perhaps, have occurred to me to regard them as a 
single form. ‘Thus the adult male is small,' often closely resembling 
var. pusillus in the size of its body, though always distinguished 
therefrom by its relatively longer appendages, the arms especially 
being very noticeably longer and slenderer, bearing about the same 
proportion to the width of the carapace as they do in adults of 
P. ceylonicus, s. str. ; whereas the female is large, being intermediate 
in size between P. ceylonicus, s. sty. and var. pusillus, and has pro- 
portionally shorter arms. Specimens in which maturity is not 
clearly indicated by the presence of embryos under the abdomen 
may therefore be very easily mistaken for immature specimens 
of P. ceylonicus, s. sty., since the proportion borne by the arms to 
the width of the carapace increases with growth. 
So far as I know it is impossible to distinguish immature 
specimens of either sex of var. gracilibvachiatus from those of var. 
pusillus; and from this it may be concluded that the arms of the 
male of the former become greatly lengthened at about the time 
when maturity is reached (as do those of the male of Charinides 
bengalensis) and that previously they are no longer than in the 
latter variety. 
In practice there is never any difficulty in distinguishing the 
adult male of var. gracilibrachiatus from the form most like it—the 
male of var. pusillus. But to distinguish adult females of var. 
gracilibrachiatus from immature females of P. ceylonicus, s. str , of 
the same size is much more difficult except, as has already been 
pointed out, when the former bear embryos. The chief differences 
between the two are :—(1) the retention in (? all) specimens of the 
latter of a distinctly spiniform rudiment of the first of the three 
dorsal spines at the distal extremity of the tibia of the arm, a 
spine which has probably already disappeared in all specimens of 
the former; and (2) the size of the semiiunar lobes on the posterior 
margin of the third abdominal segment, which are always present 
1 This difference in size and proportions shown by the two sexes is present in 
var. pusillus also, and probably in ceylonicus, s. str., as well; but in these two 
forms it is less striking, and only apparent in a series of measurements; whereas 
in var. gracilibrachiatus it is very noticeable at once--more so in fact than 
the measurements would lead one to suppose. The name gvacilibrachiatus is 
an unfortunate one now that pusillus, Poc., has to be regarded as a variety and 
not a species ; for it is from this form only that var. gractlibrachiatus is distin- 
guished by the slenderness of its arms, and not from P. ceylonicus, s. str. It was 
as a variety of P. pusillus, Poc., that gracilibrachiatus was originally described. 
