THE NEMATODE FAMILY GNATHOSTOMIBJi:. 



295 



The diameter of the oesophagus immediately behind the head 

 is 0"125 mm.; its widest diameter is 0"6 mm. and lies at about 

 0*6 mm. from its termination. 



The cervical papillse (PI. VII. figs. 30, 31) are coarse, rounded 

 knobs with their terminations directed posteriorly, each lying in 

 a small bald area among the spines. 



In the male the four large caudal papillse on each side (PI. YH- 

 fig. 32 ; PI. VIII. fig. 33) lie close together in the caudal alse. 

 No. 1 is the smallest, the others being all of about the same size 

 but varying in relative propoi-tions according to the aspect from 



Text- figure 40. 



/ c 



^natliostoma spinigemm. Body-spines: a, from the neclc, immediately behind 

 the head-bulb ; h, from the oesophageal region ; c. from behind the 

 ffisophagus (about 4 mm. from the anterior end) ; d, from about the middle 

 of the body. 



which they are viewed. Their nerves are particularly large and 

 obvious. Near the bases of Nos. 1 and 2 of these papillae lie the 

 two pairs of small ventral papillte. The cloacal opening lies in 

 front of these. 



On the greater part of the posterior 0'8 mm. of the ventral 

 surface of the caudal extremity the cuticular stride are closely set 

 with small spines (PI. VII. fig. 32 ; PI. VIII. fig. 33), the general 



