136 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



apparently so; and the nuclei are situated usually about 

 their middles. Interpolated between them are elongated 

 granular bodies without nuclei, and coarsely granular, 

 and there are a few large "goblet" bodies. The 

 epithelium rests on a coarse reticulum, the exact 

 structure of which is difficult to make out. 



Such a structure is quite consistent with the 

 interpretation of the tumours as intra-cystic myxo- 

 flbromata. They are apparently comparable in structure 

 with polypoid growths on the naso-pharyngeal epithe- 

 lium, and they are indeed present in a highly mucous 

 cavity. It is true that the stellate nucleated cells with 

 long processes, described as present in typical growths 

 of this nature, could not be seen in the large white cysts, 

 but the latter were probably too highly developed, and 

 the typical structure need not, of course, be postulated 

 for identification. 



The production of the cysts is, it seems probable, 

 to be accounted for by the occlusion, or the congenital 

 absence of the sensory canal pores. These are not very 

 numerous, and the absence of most of them would lead to 

 the production of mucus within the canals at a greater 

 rate than it could be removed. It was, of course, 

 difficult to be sure that the majority of these pores were 

 absent, but since the liquid in the large vesicles must 

 have been there under pressure, it is obvious that pores 

 could not have been present in normal number. There 

 may also have been occlusion of the canals at some places 

 by the intra-cystic growths, and it may well be the case 

 that the formation of these, together with the congenital 

 absence of pores, was the cause of the remarkable 

 dilatation of the canals. 



