140 Mammalia. Organ of Taste, 



pursue volant insects, and the antennal nose-leaves of many species 

 (RhinolophidEe) relate to the perception of atmospheric impulses 

 rebounding from surfaces near which the Bat approaches in flight. 



B. Organ or Taste. 



The Tongue is more highly developed in Mammalia than 

 in the rest of the Yertebrata. There is occasionally found 

 underlying the tongue a flattened process bifid at the apex, 

 and presenting the appearance of a second tongue, this has 

 been termed the frsenal or sublingual plate. Beneath the 

 tongue, posteriorly to the tip, is frequently found a fibrous 

 or sclerous rudiment of the ' glosso-hyal,' called ' worm,' or 

 * lyttaJ The tongue is commonly divided into a free, gusta- 

 tive, prehensile part ; and a deeper, intermolar, masti- 

 catory or deglutitional part : of these the former may be 

 developed to such an extent and have such mobility as to 

 suggest the predominance of the prehensile function, or, on 

 the contrary, may be capable of very little motion ; the 

 latter may lack the intermolar enlargement. As a rule, in 

 Mammalia, the vascular and sensitive lingual membrane ad- 

 heres closely to the muscular tissue : occasionally its sanguine 

 tint is obscured by pigment, and presents a leaden colour. 

 Horny spines are sometimes found on the superior surface 

 anteriorly, and (though very rarely) at the base, on either 

 side the mouth. 



Special. 



Frmnal Plate. 



This lingual character prevails throughout the Strepsirrliine 

 group of Quadrumana. 



The Lytta 



is well marked in the flesh-feeding Dasyuridm (Marsupialia) and 

 in the Sector ialia. 



The Intermolar Milargement 



is well marked in the Rodentia and Ruminantia; 

 is absent in Qiiadrmnana, Secforialia, and others. 



