5 1 Georgina Sweet : 



others it comes intermediate between those two species. One 

 is tempted at first sight from some of the linear proportions 

 to regard it as an immature form of Tr. serratus, but that is 

 seen to be out of the question on examination of the reproductive 

 organs, which are fully mature. On the whole, it is more satis- 

 factory to separate it from that species. So far as the material 

 in hand, consisting of three females, is concerned, its specific 

 characters appear to be the following : — 



Triodonto2:)Jiortis. — Length, ? 1'8.9 to '20. 25 mm. (average 18.4 

 mm.) ; maximum diameter ? .6 to .83 mm., average diameter 

 .48 to .66 mm., so that the body is somewhat more slender than 

 either Tr. minor or Tr. serratus, and also more pointed both 

 anteriorly and posteriorly. Head not usually separated from 

 body. Mouth collar, as in Tr. serratus, not appreciably de- 

 pressed. Parts of external leaf-crown and capsule teeth 36 to 

 44. Mouth capsule .12 to .15 mm. in length, and usually about 

 .15 mm. -in extreme diameter. It is therefore generally 

 similar in shape, though not size, to that of Tr. serratus, but in 

 the case of the longest specimen, which is similar to or inter- 

 mediate between the remaining two individuals in other re- 

 spects, the capsule was longer and narrower, as in Tr. minor, 

 though differing in size from that, being .15 mm. in length, 

 and only .11 mm. in diameter. Teeth generally .04 mm. long, 

 as in Tr. ininor, but showing the more serrated edge fotmd 

 elsewhere in Tr. serratus. In the longest individual — that men- 

 tioned above — the teeth were .048 mm. long, and the denticula- 

 tion of their anterior edges was not so marked as in the other 

 two individuals. Oesophagtis, same general shape and average 

 length as in Tr. minor; maximum diameter .16 to .21 mm., 

 minimum .07 to .084, i.e., slightly thicker than Tr. minor, 

 and less than in Tr. serratus. Excretory ojiening as in the two 

 original species, i.e., just behind the nerve ring. The cervical 

 papillae appear much nearer the median ventral line than in 

 Tr. minor or Tr. serratus. 



Female opening 1.32 to 1.54 mm. from tip of tail, and amis 

 .28 to .31 mm. from tip. In each of these respects this species 

 is intermediate between Tr. minor and Tr. serratus. In general 

 appearance the tail more closely I'esembles that of Tr. serratus 

 than that of Tr. minor. 



