308 



Memoirs of the Indian Museum. 



[Vol. VII. 



mm., and the excretory pore at 1-6-1-65 mm. (male), or 175-1-85 mm. (female), from 

 the anterior end. 



The tail of the male (fig. 44) is 1-4-17 mm. long, and tapers to a slender point. 

 There is no preanal sucker-like organ, but the oblique caudal muscles are well-deve- 

 loped. There are 16-18 pairs of caudal papillae and one median, unpaired papilla, 

 the latter and three pairs being, as usual, preanal. Of the postanal papillae two 



pairs are lateral, the rest ventral. Oc- 

 casionally one or two of the anterior 

 ventral pairs become adanal in position. 

 The members of the more posterior pairs 

 sometimes become displaced anteriorly 

 or posteriorly, so as to disturb the sym- 

 metry of the paired arrangement. The 

 spicules are short (0-5 mm.) and have a 

 maximum width of 0*09 mm. A vaguely- 

 defined mass of imperfectly chitinized 

 tissue represents the accessory piece, and 

 a fan-shaped bundle of muscles extends 

 from it to the dorsal body- wall. 



The tail of the female islong(2'25-2-6 

 mm.), straight and tapering, and ends in 

 a fine point. The caudal papillae are 

 situated at about i'6 mm. from the tip. 

 The vulva opens at 775-10-3 mm. from 

 the posterior end. The vagina is about 

 1-5 mm. long. The ova measure about 

 0-15x0-105 mm., have a shell 5' 1 thick, 

 and contain an embryo curled upon itself into a U-shape when ready for laying. 



The material from Hardella thurgi so closely resembles that from Kachuga in 

 almost all respects that we do not feel justified in erecting another species for it. 

 There are, however, certain differences, of which the most conspicuous are the greater 

 relative and absolute width of the head and the much coarser striation of the cuticle. 

 The striae in the Hardella material are about 10/' apart, whereas in the Kachuga 

 material they are so fine that accurate measurement is scarcely possible. Apart 

 from these points the Hardella material is slightly larger in almost all dimensions 

 than that from Kachuga, and has a stouter general appearance. The measurements 

 may be most conveniently given in tabular form, for comparison with those of the 

 Kachuga material : — 



Length 



Thickness (max.) 

 Diameter of head 

 Length of tail 



Fig. 44. — Falcaustra stewarti. 

 lateral view. 



Tail of male; 



<s 



9 



mm. 



mm. 



8-6-20-4 



20-2-221 



0-8-09 



0-8-1 05 



0-28-03 



0-3-0-35 



1-8-1-9 



2-5-2-7 



