OF THE TONGUES OF THE MAMMALIA. 749 



rows extend far forwards at the expense of the apical chister. 

 Those at the posterior part of the oral division of the dorsum are 

 large, hemispherical, polished, and close together. Few are pre- 

 sent on the inferior surface of the tongue. 



The conical papillte resemble those of Nycticebus tardigradus 

 in their mode of enlargement from before backwards, and differ 

 from those of Lemur and Hajxilemur. Most of the papillae are 

 cylindrical, and are surrounded by zones of interpapillary 

 dorsum. 



Lateral organs are absent. 



The following account of the subliugua (text-fig. 69) is supple- 

 mentary to those of Tiedemann (18), Otto, Vrolik (16), and 

 Gegenbaur (5). It is leaf-shaped and wrap2:)ed round the convex 

 inferior surface of the tongue, so it is concavo-convex on cross 

 section. The edges are finely crenated and the apex is sharp. 

 The denticles are smaller, less numerous, and more closely packed 

 than those of Nycticehus tardigradus, but the characters of the 

 central and lateral parts are similar in both cases. The mesial 

 dorsal crest is not so pronounced as that of some examples of 

 Xycticehus. but is equal to that of others. Both species have 

 equally mobile sublingupe, but the freedom is less than that of 

 Lemur. 



The frenal lamellte are two small, rounded processes whose 

 edges extend postero-laterally for a considerable flistance. No 

 accessory lamellpe are present. 



The median ventral sulcus resembles that of Nycticehus tardi- 

 gradus. 



Genus Perodicticus. 

 Bosman's Potto (Pe^-odicticus jmtto). 



The tongue, which narrows slightly from base to aj^ex, has no 

 apical notch and no mesial dorsal sulcus, but possesses a few 

 small, narrow transverse sulci in the posterior part of the oral 

 division of the dorsum. 



The circumvallate papillae. — Van der Hoeven (6) described and 

 figured three large papillae in a triangle with the apex behind. 

 In the specimen in the Museum of the Royal College of Surgeons 

 there are three large excavated papillae forming a triangle. In 

 my specimen there are three in a triangle, but the apical papilla 

 is divided into two large elongated parts enclosed in the one 

 fossa. 



The fungiform and conical papillae do not differ materially 

 from those of Nycticehus tairligradus . 



Lateral organs are absent. 



The sublingua is tongue-shaped and has nine apical denticles 

 as in P. iheamcs. Its strong median ventral crest is bifurcated 

 postei-iorly, and the dorsal ridge is larger and sharper than that 

 of any other species which I examined. The edges are devoid of 



