Vol. X, No. 10.] Indian Spiders. 415 



[N.S.] 



from the Darjeeling District in the Indian Museum collection) 

 are unfortunately known from immature specimens only. 

 Their genus cannot, I am afraid, be determined with certainty ; 

 but the structure of the labium and the armature of the legs 

 seem to ally them more closely with the Indian Ischnocoleae 

 than with even the most primitive Selenocosmieae, and they 

 will probably have to remain in the former group. 



In the transgangetic part of the Oriental Region we have, 

 then, one or two species of Ischnocoleae, known from immature 

 specimens only, and evidently very rare ; one species of Neochilo- 

 brackys, also apparently very rare, resembling them in the 

 absence of any stridulating organ ; and one species of the same 

 genus, apparently confined to the Nicobars, in which rudimen- 

 tary stridulating organs are present between the chelicerae and 

 the coxae of the palps. 



From the rudimentary type of stridulating organ present 

 in this species (see pi. xxxi, fig. 3) the more striking type found 



* 



w Lyrognathus w 



ing Phlogiellus, see Hirst, 1909, p. 384), Coremiocnemis, and 

 Selenotypus has presumably been developed. Of these genera 

 the first contains only three known species and appears, to be 

 confined to Assam and perhaps the Himalayas ; the second is 

 only known from one species from Australia; the third is a 

 much larger genus and extends from Assam to Australia ; the 

 fourth is only known from one species from Penang and one 

 from the "East Indies" and the fifth is only known from 

 one species from Australia. These genera are separated by 

 characters which are so slight as to be of very doubtful phylo- 

 genetic significance and may be considered here as one. 



The type of stridulating organ found in all of them is 

 figured on* pi. xxxi, fig. 4. It consists of a number of more or 

 less slender spines, more or less mixed with hairs, on the cheli- 

 licerae, and of an oval group of very numerous bacilli on the 

 coxae of the palps. Many of these bacilli are more or less dis- 

 tinctly claviform, especially those towards the middle of the 

 ventral margin of the group, but the whole depth of both 

 ends of the group consists of small hair-like bristles only. 



Although much commoner and more widely distributed than 

 the transgangetic Ischnocoleae or the genus Neochilobrachys, 

 the genus Selenocosmia appears to be much less common in Con- 

 tinental Asia at least— I am unable to judge with certainty of 

 other parts of the Oriental Region— than is the genus Chilobra- 

 chys, in which the remaining stages in the increase of specializa- 

 tion of the stridulatins organs are found. Chilobrachys , to 



which the r 



same relation as the small genera associated above with Sdeno- 

 cosmia bear to that genus, is certainly the dominant repre- 

 sentative of the group in the north-western part of the trans- 

 gangetic Oriental Region, as well as being the most highly 



noecus 



