Digestive System Special. 71 



Sectorialia. Tlie Tonsils are largest in the Digitigrada, especially 

 in Leo and some other Felidse, in which each tonsil forms a sac : 

 they are very small in the Semi-plantigrada, but large in the Plan- 

 tigrada. 



9. Tongue. 



(For Tongue as Organ of Taste, cf. Special Sense Organs.) 

 Protrusihility. 



Rodentia. The Kodentia have the least power of protruding and 

 moving the tongue, in the whole Mammalian class. 



In the Prohoscidia, Cete, and Sirenia, the Tongue is but slightly 

 moveable. 



In the In-Enamellata the tongue of Myrmecophaga affords an 

 example of one the most protrusible of all in this Class. 

 Subserving prehension. 



Cheiroptera. The tip of the Tongue is furnished in many species 

 "with long pencillate papillos at its apex, useful for probing night- 

 blowing flowers for minute Insects {e.g. in Monophyllus). In Des- 

 modus (Yampiro) the terminal papillae resemble wart-like elevations, 

 so arranged as to form a circular suctorial disk when required. 



Sectorialia. The Felidae have horny spinules on the fore part of 

 the dorsum of the Tongue, which form a powerful rasp, to cleari 

 bones. 



The act of lapping may be noticed as an instance in point. 



Artiodactyla. The Tongue of Giraffa affords an instance of one 

 long and prehensile. 



In-Enamellata. In the Edentula the most obvious office of the 

 Tongue is that of prehension : the soft viscous apex, presenting an 

 adhesive surface, is insinuated into the Ant-hills, whence the Ter- 

 mites are withdrawn, entangled in the viscid saliva that covers it. 

 Subserving distribution of food in the mouth. 



This is a common function of the Tongue, but is especially notice- 

 able in Ornithorhyncus, where the posterior or intermolar portion of 

 the Tongue is provided anteriorly with two projecting, short, conical, 

 horny bodies, which can impede the passage of unmasticated food 

 to the pharynx, and direct it on each side into the cheek pouches. 

 Subserving trituration of food. 



In-Enamellata. In the Ant-Eaters the Tongue is used to crush 

 the termites against the callous ridges [supra 5) on each side of 

 the mouth. 



