new Ascarid from an Otter. 461 



from eacli other by a deep "saddle" and projectinnf ante- 

 riorly. These teeth, when seen in prohle, are bifid. There 

 are no interlabia. At a little distance behind the bases of the 

 lips the neck is surrounded by a more or less })roniiiient fold 

 of cuticle, or " collar." In most specimens this collar is 

 turned forward, so as to form a funnel surrounding the head, 

 but occasionally it is turned back, as represented in fig. 1, 

 allowing the head to be more distinctly seen. This structure 

 gives the head of the animal very much the appearance of 

 that of a PhysaJoptera. The region of the neck between the 

 bases of the li{)s and the origin of the collar is closely beset 

 with minute spines (fig. 2, s.). This character is somewhat 

 reminiscent of the close transverse folds of cuticle seen in 

 the region immediately behind the head in many species of 



Fio;. 2. 



' 0-/mm. ' 



Cloeoascaris spinicollis. Head of female ; dorsal view. 



jh, papilla of dorsal lip ; ;?.', papilla of ventro-lateral lip ; s., spines ; 

 t., tooth of dorsal lip ; t.\ tooth of ventro-lateral lip. 



Contraccccum^ and may possibly be an elaboration of that 

 feature. 



The oesophagus (excluding the ventriculus, and measured 

 from the extremity of the lips) is 2 8-3'75 mm. long [4 mm. 

 in a specimen from Atifa.v']. The structure of the alimentary 

 canal is similar to that in Cofitraccecum. There is a small 

 rounded ventriculus, an oesophageal appendix measuring 

 l-0-l*2 mm. in length, and an intestinal caecum which runs 

 forward to within 1*25-1"55 mm. of the anterior ex(remit3\ 

 Tiie nerve-ring is situated at 0'44-0*55 mm., and a pair of 

 conspicuous cervical papilla? (fig. 1, ^:>.) at 0-52-0'7 mm. trom 

 the anterior end. The excretory pore is situated very far 

 forward, between the bases of the ventro-lateral lips. 



