System. B:?. 



Lios plain, except in one genus ( Piploscapter ) , which has hooked 

 projections on lips. Usually with two ovaries itfiabiiitidae 



Stoma not cylindrical, or if nearly so, about as long as wide. 

 Lips of some genera have distinct projections ranging in shape 

 from rounded to elaborately ornamented. .Jith one ovary, this be- 

 ing reflexed so distal end is posterior to vulva — Cephalobidae 



6. Oesophagus plectoid (with basal bulb, PI. Ill, 3). Tail tip with 

 a small projection (spinneret) Plectinae 



Oesophagus cylindroid (PI. Ill, 1) or dorylaimoid (PI. Ill, 2) 



7. Oesophagus cylindroid. Houth cavity large, subglobular, usually 

 with one or more large teeth (PI. Ill, 1) Monochidae 



Oesophagus dorylaimoid (PI. Ill, 2). Stylet often as shown in 

 PI. II, U. Some with much longer stylet, others with a tooth 

 Dorylaimoidea 



