176 TUCKERMAN: [Vol. IV. 



The epiglottis and anterior surface of the larynx contain 

 bulb-like bodies. They are almost wholly epithelial in position, 

 and measure 0.036 mm. in length and 0.024 mm. in breadth. 



The Tongue of Pteropus pselaphon. 



I examined two tongues of this species, which is peculiar, I 

 think, to the Bonin Islands. They had been kept in spirit and 

 were well preserved. 



General Description. — The organ measures 48 mm. in length, 

 14 mm. in breadth, and 10.5 mm. in thickness, and is free for 

 25 mm. from the frasnum. The extreme posterior dorsal region 

 is more or less furrowed, and at the sides of the base are numer- 

 ous large filiform papillae, curving upwards, inwards, and back- 

 wards. The anterior dorsal surface is covered with closely 

 packed, recurved filiform papillae which, when stroked in the 

 opposite direction, convey the feeling of a fine-toothed rasp. 

 The tip of the organ is nearly pointed. The under surface is 

 smooth, and marked by a median groove extending from the 

 f raenum half-way to the tip. The fungiform papillae are of good 

 size, but not very abundant. They are thinly scattered over 

 the dorsum, and are also collected into a line at the sides, just 

 above the junction of the papillate and non-papillate surfaces. 

 The circumvallate papillae, three in number, form a nearly equi- 

 lateral triangle. They are very close to the base of the tongue, 

 the papilla forming the apex of the triangle being but 3 mm. 

 distant from it. The anterior papillae are somewhat larger than 

 the posterior papilla, and are about i mm. apart. 



The Mechanical Papillce. — The compound filiform papillae 

 of Pteropus approach quite closely in their structure the corre- 

 sponding papillae of the Marsupialia, of which they appear to be 

 a modified form. They are large and prominent along the mid- 

 dle of the dorsum, but anteriorly and laterally they are smaller 

 and more delicate, the transition from one form to the other 

 being somewhat abrupt. Anteriorly there are from eight to ten 

 papillae to the square millimetre of surface. Posteriorly they 

 are somewhat less thickly set. The larger ones measure at 

 their base 0.40 mm. in diameter. A little above the base the 

 diameter is very much less. Those near the tip have a trans- 

 verse diameter of 0.20 mm., and are about 0.45 mm. in height. 

 Each papilla is seated upon a single main papillary upgrowth of 



