1915.| F.H. Gravety: Indian Mygalomorph Spiders. 283 
The three genera Neochilobrachys, Selenocosmia and Chilo- 
brachys represent three stages in the evolution of the type of 
stridulating organ found in the group. The Selenocosmia stage is 
found in the localized genera Lyrognathus (3 species), Coremtocne- 
mis (2 species), Selenostholus (1 species) and Selenotypus (1 species) 
as well as in the large and widely distributed genus Selenocosmia. 
Of these the last two are Australian, and I am not in a position 
to say anything about them. Of the desirability of keeping the 
first two distinct from Selenocosmia I am very doubtful. The 
Indian species of Selenocosmia appear to be transitional between 
this genus and Coremtocnemis, a genus which should certainly, I 
think, be abandoned. And the value of the single character by 
which the genus Lyrognathus is distinguished is probably small. 
I have, however, provisionally retained Lyrognathus as a sub- 
genus. Similarly, I am inclined to doubt the advisability of 
keeping distinct from the larger and more widely distributed genus 
Chilobrachys the mono-specific genus Orphnoecus from the Philip- 
pines. 
The genera of Selenocosmieae found in the Indian Empire may 
be distinguished as follows :— 
Stridulating organ between chelicerae and 
I palps rudimentary or absent .. Neochilobrachys. 
Stridulating organ well developed .. a 
Stridulating organ consisting of a dorsal 
crescent of fine spines, merging into 
and partially surrounding a _ ventral 
group of more or less claviform, but 
always somewhat slender, bacilli .. Selenocosmia, p. 284. 
A few of the bacilli in the ventral row 
very large and strongly claviform ; the 
number of rows, both of bacilli and of 
spines, often greatly reduced; the ven- 
tral row of bacilli usually extending 
beyond the spines in one or other 
direction... - .. Chilobrachys, p. 285. 
Genus Neochilobrachys, Hirst. 
So far as I know, only two species have yet been described 
which can be placed in this genus. They are N. brevipes (Thorell, 
1896, pp. 170-173) and N. subarmatus (Thorell, 1891, p. 13). In 
the former there is no stridulating organ between the chelicerae 
and palps. In the latter, which is represented in our collection 
by a number of specimens from the Nicobars, there is a row of 
2-6 (see Hirst, 1909, p. 388) stout spinules on the palp, and a 
group of somewhat similar but scattered and smaller spinules on 
the sides of the chelicerae close to the hair on the proximal part 
of the lower margin. ‘This stridulating organ has been figured 
elsewhere (Gravely, 1915, pl. xxxi, fig. 3). The part on the 
chelicerae has also been figured by Hirst (1909, pl. xxiv, fig. 2). 
