NEMATODE GENUS PHYSALOPTEKA. 1039 



(13) Physaloptera gracilis, sp. n. (Text-fig. 19.) 



The material consisted of about half-a-dozen specimens, all of 

 which were coiled up watch-spring like ; as no mature eggs were 

 observed, it is probable that the worms, although fully developed, 

 had not yet reached the reproductive stage. 



The cuticle shows a very fine transverse cuticular striation, 

 and it may be partly or wholly reflected over the lips. 



The cervical papillae are situated at the level of the junction of 

 the two oesophageal parts or just posterior to this ; the excretory 

 pore is situated on the ventral surface about 40 //, further back. 



The lips are simple and triangular in side view, and each is 

 surmounted by a large external tooth, ti-iangular in shape, and 

 having a spike-like internal tooth attached to its inner surface ; 

 a row of small denticles is present on either side of it, each row 

 being terminated laterally by two larger denticles. External 

 lip papiihe were not observed. 



The cesophagus is slender, and retracted from the lips, so that 

 an elongate chamber is formed between it and the lips. The 

 muscular part is slightly thinner than the following glandular 

 part, and forms in the male l/12th and in the female l/14th 

 of the whole organ. The whole oesophagus forms in the male 

 about l/7th and in the female 1/6*2 of the total length of the 

 body. The nerve ring divides the muscular oesophagus in the 

 ratio of 3 : 2, 



Feinale. 



The females vary in length from 20 to 24 mm., au'l in breadth 

 from 240 to 250 /x; the body is attenuated towards both 

 extremities, but this is only slightly evident posteriorly. The 

 tail is short and pointed, and forms l/97th part of the total 

 length . 



Tile vulva is non-protuberant, and leads into a straight vagina 

 410 yu, long by 45 /a broad; the egg-chamber which follows is 

 about as wide again as the A'agina, and is 730 /.< long ; the common 

 trunk has more or less the same dimensions as the vagina ; from 

 its posterior end the two uteri take their origin, and these pass 

 down the body more or less parallel to each other. The position 

 of the vulva divides the body into the ratio of 1 : 2. 



No mature eggs were observed. 



Male. 



The males a,verage about 19 mm. in length by 230 /x broad; 

 they are more slender than the females, and do not become atten- 

 uated towards the posterior end. 



The bursa is small, forming l/36th of the body-length ; it is 

 nearly 2| times as long as it is broad, and its width is only very 

 slightly greater than the maximum body-breadth. Its ventral 

 surface is free from cuticular protuberances, except for a small 

 area surrounding the anus. 



The lateral stalked papillse are arranged three pairs pi-e-anal 



