1 84 rUCKERMAN. [Vol. IV. 



in size, but having the same general appearance. The furrows 

 have an average depth of 0.45 mm. Serous glands are fairly- 

 plentiful, and their ducts open at all levels. The bulbs are dis- 

 posed at the sides of the folds in ten or more tiers, and also 

 occur sparingly on their upper surface. They are a trifle 

 smaller in this area than in the circumvallate papillae. 



The fungiform papillae are well supplied with bulbs, some- 

 times as many as eight being visible in a single section of a 

 papilla of this type. The epiglottis was not examined. 



The Tongue of Cants familiaris. 



General Description. — The organ possesses a considerable 

 extent of free portion. The under surface is smooth, and im- 

 pressed by a median groove extending from the fraenum half- 

 way to the tip. From this point it is continued as a slight 

 ridge to the apex. The tip, which is obtuse, is very slightly 

 bifid. The upper surface is marked anteriorly by a mesial 

 raphe. Papillae of the fungiform type are quite evenly distrib- 

 uted over the dorsum, and the usual fleshy elevations project 

 from the basal surface of the tongue. There are four to seven 

 circumvallate papillae, arranged very much as in Canis latrans. 

 The lateral gustatory organs are clearly defined. 



Gustatory Structures. 



The Circumvallate PapillcB. — The papillae vary in size, but 

 their transverse diameter is almost always greater than their 

 height. Not infrequently they are cleft vertically. The trenches 

 are narrow and uniform in width. Serous glands are not very 

 abundant. The ducts open into the trenches at their base and 

 deeper part. The bulbs are disposed on the lateral area in ten 

 to fourteen closely packed tiers. They also occur irregularly 

 on the outer wall of the trench, near its upper part. They are 

 likewise present in the epithelium lining the vertical cleft of the 

 papillae, and, according to Ditlevsen, may sometimes be found 

 on their free upper surface. They are densely packed in the 

 tiers, the tiers of the larger papillae containing upwards of one 

 hundred and thirty bulbs. In the smaller papillae the number 

 in a tier is about eighty. The bulbs vary in length from 0.060 

 to 0.071 mm., and in breadth from 0.025 to 0.035 ^nm. 



The Lateral Gnstatoiy Organs. — These organs vary from 



