108 DESCRIPTION OF THE PLATES. 



PLATE I. Fig. 2. a, PLATE I. Fig. 3. , Cells of the ineliceritous 

 mass those without nuclei being those of the 

 white external layer, the others belonging to the 

 reddish grey part of the mass, presenting nuclei 

 in various stages of developement. 

 b b Some of the latter cells, in which the nuclei 

 have become so much developed as to distend 

 their cells beyond the average size. In these 

 enlarged cells, it will be remarked, that the 

 nuclei, instead of remaining as single germinal 

 spots for each cell, have broken up into numerous 

 spots, or centres of nutrition. 



In a tumour of this kind, the cyst and its 

 contents are two distinct parts, and perform two 

 distinct actions. The cyst is the active agent in 

 withdrawing materials of nutrition for itself and 

 its contents from the vessels which ramify in its 

 outer tunic. The organs which accomplish this 

 are the germinal spots in its middle tunic, which 

 in virtue of forces of attraction in each, select 

 and remove from the capillary vessels the mat- 

 ter necessary for the formation of the cells of 

 the internal layer. These after solution pass in 

 succession into the cavity of the cyst, to serve 

 as nutriment for the contained cellular mass. 



This mass is evidently the principal element 

 of the morbid growth. The cyst is a subsidiary 

 or accessory part, arranged for the protection, 

 and due supply of nourishment for its principal. 

 The cells of which this mass consists have each 

 its own nucleus or germinal centre. These cells 

 would appear to be of two classes those whose 

 nuclei produce young cells in their interior for 

 their own nutrition, but not for the reproduction 

 of new mother cells ; and those which act as 

 reproductive individuals for the whole morbid 

 growth. These latter cells are marked b b in 

 Figs. 2 and 3, and contain numerous nutritive 

 centres or .germinal spots in their interior. The 

 flat cells of the white external layer appear to 



