400 



ON SENSATION, AND THE ORGANS OF THE SENSES. 



to have the general characters of the cutaneous papillse, but nerve-tubes have not yet been 

 detected in them. 



[Fig. 164. 



Simple papillae near the base of the tongue: A. a, concealed under the epithelium'; 6, uncovered by 

 it. Magnified 10 diameters. B. a. Arterial twig, supplying their capillary loop?, v. Vein. The vessels 

 are all contained within the line 6, 6, of basement membrane, c, c. Deeper epithelial particles resting 

 on the basement membrane, d. Scaly epithelium on the surface. The granular interior of the papilla; 

 is represented at e. c. Papillae in which the basement membrane is not visible; and the deep layer of 

 epithelium seems to rest on the capillary loop. Magnified 200 diam ] 



[Fig. 165. 



Vertical section of one of the circumvallate 

 papillce : o. Central part. 6, b. Border, c, c. 

 Fissure between centre and border. The se- 

 condary papillae are seen covered by the epi- 

 thelium. Similar papilla? are seen, d, d, on the 

 membrane beyond. Magn. S diam.] 



[Fig. 1G6. 



A. Compound papillae on the side of the foramen caecum, injected: a, a. Arterial twigs, v, v. Veins. 

 The capillary loops indicate the simple papilla; ; in one of which, b, the injected matter has been extra- 

 vasated witliin the basement membrane of the papillx, the outline of which is thus distinguished, c. 

 Capillary plexus, where no papillaj exist, e, e. External surface of the epithelium of the papilla. 

 Magn. 15 diam. 



B. One of the simple papilte of A : a, i>, v. Arterial and venous sides of the capillary loops. b,b. 

 Basement membrane, d. Deeper epithelial particles resting on the basement membrane, s. Scaly epi- 

 thelium on the surface. Magnified 300 diameters.] 



