Habits of the Ant-eater of the Cape. 



169 



The tongue is from 10 to 12 inches long, when stretched 

 out. The mucous membrane of its upper surface is rough 

 and of a file-like feeling, when the finger is passed backwards 

 along it. There are three papillse near the base, situated in 

 the form of a triangle. On the outside, at about the posterior 

 half, are the conjoined palato and stylo-glossus muscles, and 

 internally to them, the lingualis, running from the base to the 

 tip of the tongue ; and at the posterior fourth in the mesial 

 line is the lingual attachment of the mylo-hyoglossus muscle. 

 The lingual sensory nerve is very large, and lies in a groove 

 between the mylo-hyoglossus and the lingualis, and after 

 passing the former, the two nerves lie side by side in the 

 mesial line between the two linguals. The muscular nerves 

 branch off; the fifth enters the mylo-hyoglossus, gives branches 

 to it, and then passes forwards alongside the lingual nerve. 

 The muscle to which I would attribute the protruding action 



of the tongue, or the Extensor 

 lingua, consists of perpendicular 

 fibres passing from the thick 

 mucous membrane of the upper 

 surface and sides, to the cellular 

 tissue investing the linguales 

 muscles ; this occurs throughout 

 the whole length of the tongue, 

 and engrosses more and more of 

 the comparative thickness of the 

 tongue towards the point from 

 the base. The best way of de- 

 monstrating the course of its fibres, which are otherwise 

 visible enough, is to incise the tongue either transversely or 

 longitudinally, just through the thickness of the mucous 

 membrane, and then tear open the incision. The laceration 

 is easy, and goes in the direction of the fibres to their attach- 

 ment at the upper surface of the lingualis. The contraction 

 of this muscle, in all its body, will produce a contraction of 

 the diameter or thickness of the tongue, and at the same time, 

 from the consequent increase of the diameters of the sepa- 

 rate muscular fasciculi, must the tongue elongate. It may 

 be otherwise stated, if the mass of the tongue is decreased in 



1. The mucous coat. 



2. The perpendicular fibres. 



3. Nerves and vessels. 



4. Linguales and genio-hyoid. 



5. The palato-glossus. 



