336 r. Tuckerman, 



Gustatory Structures. 

 The C ir cumi aliate Papillae. — The papillae are 0,40 mm. in 

 diameter and 0,95 mm. in height. Their upper surfaces are more or 

 less flattened, and their sides are vertical or nearly so. The trenches 

 encircling them are narrow and very deep. Serous glands are but 

 sparingly present, and their ducts open at oi- near the bottom of the 

 trenches. At the lowei- part of the papillary axis are a few isolated 

 ganglion cells. The taste-bulbs are disposed on the lateral area, often 

 nearly filling it. They also occur to some extent on the free surface of 

 the papillae. The average number of tiers appeals to he about eighteen 

 (though there may be twice as many), a well-filled tier containing from 

 sixty to seventy bulbs. The bulbs show some indications of a neck, 

 and measure 0,054 mm. in length and 0,030 mm. in breadth. No bulbs 

 were detected either in the fiuigiform papillae or the epiglottis. 



The Tongue of Dasypus villosus. 



I received three specimens of this tongue. They had been kept 

 in spirit, and the tissues were in a fair state of preservation. 



General Description. — The organ is long and narrow, and 

 tapers gradually to a point. It measmes 81 mm, in length, and is 

 perfectly fi'ee for 50 mm, from the fraenum. At its posterior part it 

 is 12 mm. in breadth and 14 mm. in thickness. The under surface is 

 marked by a distinct median ridge leading from the fraenum to the 

 tip. The extreme basal portion of the organ is bent somewhat ab- 

 ruptly downwards, as in Dasyhus peha. The upper surface is quite 

 densely papillate over nearly its entire area. Papillae of the fungi- 

 form type are sparingly scattered over the dorsum and sides of the 

 tongue. The two circum vallate papillae are on the same transverse 

 line, and are set quite close to the lateral margins of the organ. They 

 are 7,3 mm. apart, and 17 mm. from the base of the tongue. There 

 is a lateral gustatory oigan at each side of the base. The organs are 

 marked externally by three or four small, irregular openings, running 

 transversely to the long diameter of the tongue. 



The Mechanical Papillae. — These papillae ditter in some re- 

 spects from the compound filiform papillae of the marsupial tongue. 



