Volume //.] December, lyoo. \_No. J. 



BIOLOGICAL BULLETIN. 



THE OESOPHAGEAL GLANDS OF URODELA. 



R. R. 1-iKNSLEY. 



FOR a long time the only known instance of glands occurring 

 in the oesophagus of an Amphibian was the familiar pepsin- 

 producing glands of the frog's oesophagus, discovered as early 

 as 1838 by Bischoff (i). In 1853 Leydig (8) described the 

 occurrence of saccular glands in the oesophagus of Proteus 

 anguineus, and, more recently, similar glands have been dis- 

 covered by Kingsbury (5) in the oesophagus of Necturus 

 maculatus. 



In no other Batrachian has investigation revealed the exist- 

 ence of glands in the oesophagus, unless,, indeed, as Klein (6) 

 suggests, the highly branched glands found at the junction of 

 oesophagus and stomach in Triton, and termed by Langley (7) 

 the anterior oxyntic glands, are such. 



Naturally, considerable interest has been evinced in the 

 question of the homology of these glands one with another, 

 and with those of the higher vertebrate classes. 



In order that the problem to be solved may be clearly under- 

 stood, it may be as well to recapitulate briefly the facts as they 

 appear in the forms so far investigated. 



In the frog, leaving out of consideration the pyloric glands, 

 there are two kinds of glands occurring in the foregut. The 

 oesophageal glands occur under a ciliated epithelium, and are 

 large compound glands, consisting each of a number of short 

 tubular acimi lined by pepsin-secreting cells, opening into a 

 common duct lined by transparent mucous cells. As we pass 



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