Nematode found in Stomach of Copper-head Snake. 30 



The continuous horizontal line of the formula may be 

 regarded as the animal itself, the numerators indicatino- the 

 dimensions in length at successive stages from the head end, 

 and the denominators showing how the body thins, or 

 thickens at each successive stage. 



Summing up the information conveyed by the formula 

 alone, we have a worm 144 mm. long, somewhat cylindrical 

 in form, and from the base of the neck towards the anterior 

 extremity there is a gradual tapering. In the posterior 

 portion of the body, there is a very considerable tapering 

 from the vulva to the anus, as indicated by the comparison 

 of the figures 1, 2, and 4. 



The numerators denote that the head is relatively small; 

 that the nerve-ring is situated towards the anterior end of the 

 neck ; that the vulva does not occupy a central position in 

 the body, but is situated in the posterior half; and that the 

 anus is almost, but not quite, at the posterior end of the body. 



Only one specimen having been met with, and the male 

 unknown, it would be premature to fix the exact systematic 

 position. 



Note. — The nematode formula of Dr. Cobb is full}^ 

 explained in Ag. Gaz. N.S.W., vol. I, part I, p. 131. 



EXPLANATION OF PLATE. 



All drawn with the camera, except ovary in Fig. 9, which 

 is sketched in. 



L Ascaris sp. (1) 



2. „ profile, posterior extremity. 



3. „ ventral view of posterior extremity. 



4. ,, near middle, showing width of lateral field. 



5. „ oesophagus and nerve-ring. 



6. „ lips and papillse (p). 

 7 and 8.,, lips. 



9. „ 9 sexual organs, one branch only shown. 



10. „ eggs (spherical). 



