28 



THE ROUNDWORMS OF DOMESTIC SWINE. 



not a series of parallel bands, as described by Von Linstow (1879b) , or a 



continuous spiral, as described by Von Drasche (1884a), Railliet and 



Henry (191 Ib), and Ciurea (1912). 



Railliet and Henry (191 Ib) mention two asymmetrical cervical 



papillaB, the right papilla being 220 /* and the left 420 JM from the 



anterior end. As seen by the present 

 writer the left papilla has a broad 

 base and a blunt point and pene- 

 trates the cuticle 281 /i from the an- 

 terior end, or a little anterior of the 

 base of the cephalic inflation. The 

 right papilla was not seen by the 

 present writer, but on the right side, 

 not far from the location of the papilla 

 as given by Railliet and Henry 

 (191 Ib), the excretory canal opens. 

 The end of the canal is a slender 

 tube penetrating the middle lateral 

 wing and looking not unlike a long 

 stalked papilla (fig. 18). Its true 

 nature has been shown by Ciurea 

 (1912), who made a cross section of 

 the. worm at this point. The lateral 

 situation of the excretory pore is ap- 

 parently unique among nematodes, 

 the usual situation being ventral. 



The lateral cuticular wings unite 

 just posterior of the base of the ce- 

 phalic inflation (fig. 18). Here the 

 cuticle forms an inverted pocket like 

 the handle of a table drawer (fig. 27). 

 The lateral cuticular wings are densely 

 striated at the base, giving them a 

 puckered appearance. Although the 

 cuticle of the entire body is striated, 

 these striations appear more promi- 



ey 



wings; n. r., nerve ring; ph., pharynx. 

 X 150. (Original.) 



lomm 



FIG. 27. Physocephalus sexalatus. Lateral 

 view of anterior end of body. c. cut. inf., 

 cervical cuticular inflation; cut., cuticle; 

 es., esophagus; ex. p., excretory pore; lab. -, , . 



P., labial papiii; i. c. ., lateral cuticular nently on the lateral wings, particu- 

 larly at their base, than elsewhere. 

 The esophagus, about four-fifths of 

 the length of the lateral wings, is densely striated transversely, 

 with a very narrow lumen; nerve ring 439 // from the anterior end 

 (fig. 18). The intestine is more or less convoluted throughout its 

 course, especially posteriorly. 



The male (fig. 28) is about half the length of the female, but as 2 

 to 3 mm. of the posterior end is twisted into a spiral, its apparent 

 length is much shortened. 



