264 THE SALAMANDER 



prevomerine teeth. These grooves and the median pit are easily- 

 discernible with a lens, but the actual openings of the glands must 

 be sought in transverse sections under a microscope. 



Kingsbury (i 9 1 2) in Salamandra atra and various other Amphibia 

 finds, in as many as twelve regions of the mouth and pharynx, 

 aggregations of cells of a lymphoid character which he regards as 

 analogous to the tonsils of Amniota. A detailed discussion of this 

 question lies outside the scope of the present work, but the position 

 of the following four patches, which Kingsbury finds to be definite 

 and constant, may be mentioned. 



(i) The choanal in the roof of the mouth immediately posterior to 

 the internal narial opening. 



(ii) The lateral^ situated laterally in the pharynx in the general 

 region of the articulation of the jaw. 



(iii) The sublingual lying lateral to the tongue over the expanded 

 cerato-hyal. 



(iv) The preglottideal on the floor of the mouth just in front of the 

 glottis. 



It must be pointed out that Kingsbury's results are of a general 

 nature and have not been checked specifically for Salamandra 

 maculosa. 



As in Amphibia generally the eyeballs are not separated from the 

 palate by any skeletal element, and their form is therefore plainly 

 visible as a pair of convex bulges on the roof of the mouth. Just in 

 front of these may be seen a pair of relatively large oval openings, 

 the choanae or internal nares. 



3. The Pharynx and Oesophagus. 



The pharynx leads directly from the mouth as a wide tube. It is 

 richly vascular and unmarked by any Eustachian tubes and passes 

 imperceptibly into a wide oesophagus (oes.) which in turn leads, also 

 without any sharp line of demarcation, into the stomach. The external 

 walls of both oesophagus and stomach, and in fact of the whole gut 

 also, are smooth, but the internal walls are variously corrugated, 

 each section of the gut having its own particular pattern. Thus the 

 distinction between the oesophagus and stomach is clearer internally 

 than externally, the lining of the former being thrown into deep 

 longitudinal folds, while the folds of the stomach are marked by a 

 relatively shallow, wide-meshed, irregular network, of which the 

 longitudinal members are the more prominent. The mucous epithe- 

 lium is velvety, and when scraped off the blood capillaries are found 

 to be fiat and not raised into loops. 



