SEA-FISHERIES LABORATORY. 119 



growths was cut out and sectioned. As a rule, these 

 secondary tumours and pigment spots measured about 

 1 cm. in diameter. 



There was no obvious indication of emaciation in the 

 parts of the fish seen by me or Mr. Bailey, who sent the 

 specimen. 



One of the metastases sectioned, fig. 4, PI. II, 

 shows clearly the Zocws of the growth. The epidermis 

 has gone from over the entire surface of the tumour and 

 is seen only at the edge, on the adjacent skin. Three or 

 four distinct layers of coarse connective tissue fibres are 

 seen in the section, and the cells of the neoplasm appear 

 to take origin in the finer areolar tissue between the more 

 superficial layer of these coarse fibres and the epidermis, 

 and in the deeper layers of loose connective tissue. The 

 darkly shaded region in tlie figure represents the 

 distribution of the sarcoma, and it is indicated by the 

 figure that it is initiated between the coarse connective 

 tissue bundles. These latter fibres themselves do not 

 grow or proliferate in any way, but they become broken 

 down by the growth between them of the cells of the 

 sarcoma, and probably suffer from lack of nutrition. 

 The lower layers of the dermis, the deeper areolar tissue, 

 and the structures included in it, nerves, blood vessels, 

 sensory canals and lymph vessels are not involved and 

 are normal in structure. 



The same general distribution is seen in the sections 

 of the fully developed tumour, though the relations are 

 less easy to make out than in the metastasis. Furthest 

 away from the growing edge it is only the areolar tissue 

 directly underneath the epidermis that is involved : here 

 one sees the intrusive sarcomatous cells loaded with 

 melanin granules. Nearer to the centre of the tumour 

 all the fine tissue between the coarse fibres becomes 

 I 



