- 7 8- 



(c) Section of Tongue showing Fungiform Papil- 



Ue. 



Portions from the posterior part of a dog's tongue, known to, 

 contain fuugiform papillae, were hardened in mercuric chloride, 

 stained in Pelnfield!s hsematoxylin, embedded in paraffin, and sec- 

 tioned at right angles to the long axis of the tongue. The sections 

 were fixed to cover glasses and counter stained in eosin, dehydrated, 

 and cleared in oil of bergamot and xylol. Mount on balsam. 



Study first under low power. Search for the broad 

 conical projections of the mucosa, composed of a rather 

 dense fibrous tissue on which many secondary papillae are 

 seen. They are covered with stratified pavement epithe- 

 lium. Many fillit'orm papillae will also be seen in this 

 section. Observe the arrangement of the muscle fibres. 

 The preparation will also show arteries, veins, and nerves 

 in section. Sketch one fungiform papilla as seen under 

 high power. 



(d) Taste Buds. 



The papilla foliata of a rabbit was hardened in mercuric 

 chloride, stained in Delafield's hsematoxylin, embedded in paraffin, 

 and sectioned at right angles to the transverse ridgps seen on the 

 papilla. Mount in balsam. 



The taste buds are embedded in the epithelium lining 

 the furrows between the ridges. In the muscular and con- 

 nective tissue below the papilla foliata small serous glands 

 will be seen in section. Sketch two ridges with the inter- 

 vening furrow and taste buds as seen under high power. 



(e) Mucous and Serous Salivary Glands. 



Small pieces taken from the submaxillary and parotid glands 

 of a dog were hardened in murcuric chloride, pieces of each gland 

 embedded side by side in paraffin (so that one section will pass 

 through both glands), and sectioned. The sections were then fixed 

 to cover glasses, stained in Haidenhain's iron-lack-hgematoxylin, 

 dehydrated, and cleared in oil of bergamot and xylol. Thus on 

 each cover glass are sections of both submaxillary and parotid 

 glands. Mount in balsam. 



Study first under low power. The less deeply stained 

 section is the mucous (submaxillary) gland. Both glands 

 have the same general structure. The acini are grouped 

 into lobules which are held together by a loose fibrous tis- 



