THE NEMATODE FAMILY GNATHOSTOMID^. 



265 



re-examining two of the original specimens. These were, unfor- 

 tunately, both females, no male being available, but we have 

 been able not only to confirm our suspicions as to the species 

 belonging to the genus Tanqua, but also to compare the type- 

 specimens with our own examples from Indian snakes, and to 

 satisfy ourselves that these belong to the same species. 



This form appears to be very variable in size, while constant 

 in other characters. The extreme size-variations we should 

 certainly have been inclined to legard as being at least sub- 

 species, had we been able to find any definite anatomical 



Text-fisrure 17. 



Text-figure 16. 



Text-fig. 16. — Tanqua anomala. Head and oesopliageal region ; lateral view. 

 (The cervical sacs are unusually short in this specimen.) 



Text-fig. 17. — Tanqua anomala. Anterior end ; nearly ventral view. 



dijBerences in support of this view. The type-specimens in the 

 Colombo Museum, from Tropidonotus piscator in Ceylon, are 

 among the smallest, while the largest examples we have seen 

 came from a snake of another genus {Homcdopsis huccata) in 

 Siam. 



The anterior part of the body (text-fig. 16) is tapering. The 

 lips (text-figs. 17, 18) are large and prominent, and more conical 



