ASCARIS TYPICA. 



137 



striae seen in some other species. Tiie posterior edge of each cuticular band projects 

 prominently beyond the anterior edge of the one next succeeding, so that the edge of 

 the worm appears distinctly serrate. The oesophagus (fig. 44) is divided into two 

 portions ; an anterior portion about 4'"'" long by 0.4"'" in diameter at its distal end. 

 This part, which is extremely muscular, is followed by a second portion of different 

 histological appearance and wider lumen, measuring about 1.25"°™ long by 0.25""' in 

 diameter, and in all cases examined it was sigmoid. The distal end of this body 

 leads directly into the anterior end of the intestine; both oesophageal and intestinal 

 caeca are absent. 



Fig. 49. 



The adult males (fig. 37) vary from 31 to 38""° long and 1 to 1.5°"" in diameter; 

 the proximal extremity is more attenuate than the distal end (flgsV 45-47), which is 

 curled, flattened dorso-ventrally, and provided with lateral alae; the postanal portion 

 is conical and bent vertically. Nine to ten, or possibly eleven, pairs of postanal papillae 

 are present; of these, three occasionally two or two and a half pairs of conical papillae 

 are nearer the tip, while six to seven, possibly eight, i)airs of shorter papillae are 

 nearer the cloaca. The arrangement of the praeanal papillae varies greatly in different 

 specimens ; there may be over seventy-five on each side, arranged in three irregular 

 rows. The cloaca is 0,27""° from the tip of the tail, and extruding from it may 

 frequently be seen the spicules. The latter are of very unequal size, the left spicule 

 (3°"") about three times as long as the right (0.96""" long). 



