18 Cobb — Nematodes, mostly Australian and Fijian. 



Ket to the Males Described. 



Pharynx with two large teeth 9. JluviatiUs. 



Pharynx with only one large tooth. 



Spicula unknown - 1%. filiformis. 



Spicula not exceeding the anal body-diameter in length. 



Proximse furcate 12. macrodon. 



Proximse cephalated by constriction, not furcate 16. similis. 



Proximse neither cephalated nor furcate 8- graminum. 



Spicula exceeding the anal body-diameter in length. 



Tail 40% or so 10- trichuris. 



Tail 30 % or so. 



Pharyngeal tooth basal 6. australis. 



Pharyngeal tooth not basal. 



Body longitudinally striated •• H- striatus. 



Body not so striated 2. parvus. 



Tail about 15 % or 20 %. 



Length not exceeding 1 mm. 



Proximse of the spicula geniculate .. 17. longicauda. 



Proximse of the spicula not geniculate. 



Throat or pharynx with a well developed tooth 7. minima. 



Throat or pharynx with no well developed tooth 14. gracilis. 



Length 2-5mm ••■• 13. rivalis. 



1. D. viviparus, von Linstow. \l \ ^2-i^2"iT3 is-n-"- Cuticle finely transversely 

 striated. In front of the anus three, and on the anterior third of the tail five, 

 prominent rings encircle the body. On the ventral side of the hindermost of these 

 rings occurs a circular organ with a circular centre, the whole being as wide as the 

 tail at that point. Head truncate, but with a broad projection at the mouth ; setae 

 none ; lips uncertain ; pharynx as deep as the head is wide and two-thirds as wide as 

 the head, constricted in the middle, with some teeth of unequal size at the base ; 

 pharyngeal swelling elongated, tapering behind; median bulb considerably behind the 

 middle of the neck ; posterior swelling much elongated, tapering anteriorly ; tail 

 conical, tapering from in front of the anus ; caudal glands none ; viviparous ; embryos 

 slender, without the chitinous structure on the head. 



Hab. — Water plants, Germany. It is perhaps questionable whether this is a 

 Diplogaster. 



2. D. parvus, n.sp. Female unknown. 1-3 \i%ii — 21 — Fa ■^"™- Neck conoid; head 

 truncate, with six lips, each with one papilla ; pharynx elongated, crooked, anterior 

 part wider, the tooth appearing as a prominence and without a distinct and projecting 

 apex ; oesophagus slender, the anterior part being only one-third as wide as the neck ; 

 bulbs one-half as wide as the neck ; intestine three-fourths as wide as the body ; 



