304 



Memoirs of the Indian Museum. 



[Vol. VII, 



F. falcata (v. Linst., 1906), from Oeoemyda trijuga, 



F. lambdiensis, Seurat, 191 8, from Clemmys leprosa, 



F. siamensis, Baylis, 1920, from Hieremys annandalei : 

 while we may also refer to it 



F. [Oxysoma] kachugae (Stewart, 1914), from Kachuga lineata. 

 The hosts of all these species are tortoises. Of the new species to be described, 

 two are from tortoises and two from a fish Some of them show considerable diver- 

 gence from the typical characters, and will necessitate some modification of the 

 generic diagnosis. We do not, however, feel justified in splitting up the genus at 

 present, as it would be hard to find a clear and satisfactory dividing-line between 

 the typical and the atypical species. 



Taking first the forms that depart least from the characters of the genotype, we 



have the following : — 



Falcaustra testudinis, sp. no v. 



(Fig- 39-) 



Host : Testudo elongata. Locality: Assam (Tura, foot of Garo Hills). 



This is the smallest species hitherto met with. The male measures 10*2-10*4 mm. 



in length and o*6 mm. in thickness; the female 9*2-11*5 mm. and 0*6-0*75 mm. 



respectively. The diameter of the head is 0*15-016 mm. This is followed by a 



slightly narrower neck. The buccal cavity measures about 0*05 mm. in length and 



0"03 mm. in diameter. The distinct 

 anterior division of the oesophagus, to 

 which we shall hereafter refer as the 

 "pharynx, " is 0*i3-0'i4 mm. long. The 

 entire oesophagus, from the extremity 

 of the head to the back of the bulb, 

 measures 17-2*1 mm. The bulb consists 

 of two swellings separated by a narrow 

 neck ; its length is 0-4-0*45 mm. and the 

 diameter of the larger (posterior) swelling 

 0*26-0*27 mm - The prominent cervical 

 papillae are situated at 1*03-11 mm., the 

 nerve-ring at 0*44-0*45 mm., and the 

 excretory pore at 1*22-1*26 mm., from 

 the anterior end. 



In the male the tail is 081 mm. lone, 

 and there is no preanal sucker-like organ. 

 The caudal papillae (fig. 39) consist of 

 the typical eleven pairs and one unpaired preanal papilla. Nos. 1 and 2 are close 

 together, ventral ; No. 3 lateral ; No. 4 isolated, ventral ; No. 5 ventral ; No. 6 lateral, 

 at about the same level as No. 5 ; Nos. 7 and 8 at the sides of the cloaca and close 

 together. The spicules measure o*8 mm. in length and 0*07 mm. in greatest width. 

 The chitinized portion of the accessory piece is 0*15-0*17 mm. long. 



Fig 39. — Falcaustra testudinis. 

 male ; lateral view. 

 a.p.. accessory piece. 



■Posterior end of 



