1899] 



DISTRIBUTION OF THE ARACHNIDA 



217 



difference between the species of two areas may, if desirable, be 

 regarded as of sufficient value to warrant their separation as 

 geographical regions. Similarly the occurrence of the same specific 

 form in two adjacent islands, for example, does not necessarily imply 

 that the separation of the two islands is of recent date. 



Distribution of the Uropygi. 



The tailed Pedipalps or Uropygi are divided into two sub- orders, the 

 Oxopoei and the Tartarides. The latter is a group that is but little 



180 160 140 130 IOOL.n < »60.f'j- m 60 40 20 20 4$ SOLmgr 80~fU-a]QO 120 140 160 \ 180 | 



Map illustrating the geographical distribution of the Uropygons Pedipalps. 



known and comprises some very small degenerate forms that have been 

 met with only in Burma, Ceylon, and Venezuela. No doubt they will 

 be discovered elsewhere in the Tropics when adequate search has been 

 made. There is, indeed, a dubious record of a species from Liberia in 

 West Africa ; but until the group has been further investigated, it cannot 

 be considered a very important factor in the study of zoo-geography. 

 Two genera are recognised : Tripcltis, with a slender cylindrical telson, 

 discovered in Ceylon and Burma, and Schizonotus, with an expanded, 

 somewhat spatulate telson, in Ceylon and Venezuela. 1 



The existing forms of Oxopoei are referred to a single family, 

 the Thelyphonidae, divisible into two sub-families, each represented 

 by several genera, which are distributed over the south - eastern 



1 This genus has also been introduced into conservatories in Europe, in connection with 

 exotic plants. 



