NEMATODE GENUS PHYSALOPTERA. 



1041 



(14) Physaloptera longissima, sp. n. (Text-fig. 20.) 



The material consisted of about two dozen specimens, some of 

 which were still immature. The specimens are remarkable for 

 their slenderness, the largest females having a thickness of less 

 than 500 p.. The body shows very little attenuation towards the 

 extremities. 



The cuticle is finely striated transversely, and in some cases it 

 forms a small swelling round the head, whereas in others it is 

 reflected over the lips. 



The cervical papillae and excretory pore occupy a very anterior 

 position, the former being found at the level of the nerve ring, 

 and the latter half-way between the nerve ling and the level of 

 the base of the muscular oesophagus. 



Text-fip-ure 20. 



IBhysalo-ptera longissima, sp. n. 

 A = Ventral view of cephalic extremity. 

 B = Caudal extremitj' of male. 



The lips are rounded, and each carries only a single tooth, 

 namely the external median ; this tooth is triaiigular in shape, 

 and has its tip slightly recurved outwards. Each lip carries two 

 outer papillge. 



There is no difference in diameter in the two oesophageal 

 parts, the tv/o merging gradually into each other ; the whole 

 organ attains l/7'6 in the female and l/6"6 in the male of 

 the body-length : the muscular part, which is encircled in its 

 middle by the nerve ring, forms nearly l/8th of the whole 

 organ. 



Female. 



The largest females are 30 mm. long by 438 /.< broad, and 

 possess a vulva which is situated just in front of the middle of 



