Witton har VOLULION ANDAs TRIBUTION 
OF THE INDO-AUSTRALIAN, THELYPHONI- 
DA WwW bare N- OVD BS? Oia Eva) 1S = 
EENCILVE CHAR AG PER SOk 
Vea RRO st 5 bre C Eis 
By F. H. Gravety, M.Sc., Assistant Superintendent, Indian 
Museum. 
(Plates I—IV.) 
It has recently been shown (/J.A.S.B. [n.s.] X, 1914, pp. 20I- 
210, pl. xxiv) that in several groups of animals the extraordinarily 
rich fauna of the Malay Archipelago is composed of highly spe- 
cialized species, whose more primitive ancestors are represented 
by species found at the present day mainly in the surrounding 
countries. And it has been suggested that this is due to the 
conditions found in the Archipelago favouring the rapid evolution 
of highly specialized species, these replacing the less specialized, 
and tending to force them outwards towards, or even beyond, the 
borders of the combined Oriental and Australian Regions. In 
this way it is possible to explain the fact that primitive species 
found in Ceylon are sometimes more closely related to species 
found in Australia than to their allies found in the intervening 
countries. 
The groups specially referred to were Passalid Coleoptera, 
Crinoids, and Thelyphonids. But the reference to Thelyphonids 
was based only on a short preliminary note published in the 
Proceedings of the Asiatic Society of Bengal for August I0QITt. 
The object of the present paper is to supplement this note by 
gathering together all available information bearing on the sub- 
ject. 
An excellent account of the Thelyphonidae was written by 
Kraepelin and published in ‘‘ Das Tierreich”’ in 1899. Although 
several new species have since been described a complete synony- 
mic revision of the group is as yet uncalled for, and would be 
largely a repetition of Kraepelin’s work. 
In many species, however, the distinctive characters are most 
difficult to describe with precision and determinations have to be 
based largely on comparison with authentically named specimens 
or accurate figures. Opportunity has therefore been taken of 
publishing with this paper a number of figures which seem to be 
required. 
The numerous specimens of certain of the commoner species 
of Thelyphonidae possessed by the Indian Museum have shown 
that the characters supposed to be distinctive of different species 
F 
