100 



CCELELMINTHA. 



Fig. 43. 



sense of touch and its modifications, to which the perception of 

 taste and odours must be referred. 



(133.) The Linguatula teenioides (fig. 43, 1) is the first example 

 which we shall select to illustrate the structure of the Ccelel- 

 mintha. This ento- 

 zoon, which is gene- 

 rally found to inhabit 

 the frontal sinus of 

 quadrupeds, is about 

 three inches in length, 

 and as many lines in 

 breadth, at the broadest 

 part of its body. In 

 external form it has 

 some resemblance to 

 the tape- worm, being 

 divided into slightly im- 

 bricated segments; but 

 in its internal structure 

 it is widely different, 

 especially as relates to 

 the arrangement of 

 the generative organs, 

 which, instead of being 

 multiplied until they 



are nearly as numerous as the segments of the body, ( 117,) 

 form but one continuous system. 



The Linguatula is invested externally with a delicate cuticle, 

 easily separable by maceration, so as to peel off as represented in 

 the figure.* 



(134.) Around the mouth (fig. 43,1, a), are several oval pits or 

 cavities containing as many sharp, recurved hooks by which the an- 

 terior extremity of the body is securely attached to the walls of the 

 frontal sinus, and the mouth retained in a position adapted to 

 secure an adequate supply of nutritive material. 



The mouth itself is a simple aperture, from which a short and 

 narrow ossophagus leads to a dilated cylindrical stomachal cavity, 

 (fig. 43, 2, a,) that forms a somewhat capacious receptacle for 

 food ; to this succeeds a straight intestinal tube (/}> which tra- 



Owen, Transact. Zool. Soc. vol. i. 



