OBSERVATIONS ON STRUCTURE OF CELLS AND NUCLEI. 153 



where it embraces the '' crescent," so that the two structures, viz. 

 membrana propria with staff-shaped (profile view) nucleus, and 

 crescent composed of granular uninuclear cells, are here seen side 

 by side; and we' are therefore enabled to say that these mucous 

 glands possess granular parietal cells just like the submaxillary 

 gland. If I compare alveoli whose mucous cells and lumen are filled 

 with mucin, with alveoli that are not in a state of secretion, I do not 

 see any perceptible change in size of the crescents ; in the sub- 

 maxillary gland we saw that their size is increased ; but I should 

 not like to pronounce definitely on this point, because the relatively 

 small number of the crescents is not very favorable for determining 

 that. However this maybe, thereis at any rateno co??5/;?c?<c»?<5 altera- 

 tion, for then we should most probably not fail to discern it. 



Much greater, however, than in the cesophagus is the number 

 and size of the " crescents," composed of polygonal granular^ 

 parietal cells, in the glands of the pharynx of young dogs, in 

 which, side by side and directl>/ contimioiis with alveoli con- 

 taining a fair number of granular parietal cells, there are others 

 that are entirely composed of granular cells, polyhedral in shape 

 and possessed of a rounded or oblong nucleus. Alveoli of this 

 kind are smaller than the ordinary alveoli, and possess either 

 only a trace of a lumen or hardly any lumen at all. We have 

 here the same appearances that I mentioned on the occasion of 

 the submaxillary gland of young animals. That also in the case 

 of the pharynx the alveoli composed entirely of granular cells 

 represent a stage of development, and are not alveoli with " ex- 

 hausted " mucus cells in the sense of Lavdowsky, nor alveoli in 

 which the mucous cells liave been destroyed and replaced by the 

 parietal cells, is proved by the following facts : — [a) They are 

 present in great numbers in the young animal, and only in the 

 most peripheral parts of the gland-tubes; {b) they are con- 

 nected both with tubes in which the gland cells are in a state of 

 rest, and with such in which these are charged with mucin. 



In the epiglottis of the dog the same condition obtains as 

 regards the mucous glands, viz. there are tubes lined with well- 

 developed mucous cells differing in no way from those of other 

 mucous glands ; in addition to these we have tubes that contain 

 ''crescents^' of granular cells; and finally in connection with 

 these we find alveoli which, to a greater extent or almost entirely, 

 consist of ''granular" cells. 



In the trachea of cat the number of tubes lined only with 

 granular cells arranged round a distinct lumen is very great 

 indeed. The ordinary mucous cells are in this animal fine 

 columnar cells, which differ from those of dog, inasmuch as 



' I need hardly repeat that their substance is not in reality granular, but, 

 as in the previous instances, a dense network. 



