SEA- FISHERIES LABORATORY. 139 



but the skin round its margin was slightly raised and thickened. 

 Near this large sore were some smaller ones about 1 to 2 cms. 

 in diameter. Unlike the larger lesion, these were rather deep. 

 In all cases the exposed tissue was creamy in colour and 

 obviously not muscular. There was no pus or blood, and the 

 wounds were quite clean ones. 



On feeling the rest of the fish, firm and hard nodular 

 masses could be detected beneath the skin, although they 

 were not visible in any case. On cutting down, these were seen 

 to be rounded or egg-shaped masses, embedded in the muscular 

 tissues. They were opaque and white in colour, usually hard, 

 but in some of them the internal parts had suffered necrosis, 

 and had liquefied. These growths were about 2 to 6 cms. in 

 diameter. 



Fig. 3, PL II, represents a vertical hand-section through the 

 large lesion. The normal integument is shown at the upper 

 edge of the section, both on the right and left hand sides : on 

 the left, part of a scale is shown in the section. Below there are 

 normal bundles of muscle fibres running in the plane of the 

 paper. The stippled part of the figure represents the locus of 

 the abnormal growth. It occupies a situation below the 

 abraded surface of the body forming the lesion. There are 

 also some other growths in connection with the main one or 

 independent of it. 



Fig. 5, PL IV, represents a section through a small part 

 of one of these growths as seen under a high-power oil-immersion 

 lens. The tissue is of the " fibro-sarcomatous " type, that is 

 its chief constituent is perhaps a coarse and dense fibrous 

 reticulum as shown in the section. In some places this fibrous 

 tissue is the predominant one, and the growth has all the 

 characters of an ordinary fibroma, but in other places, as in 

 the part figured, the tissue consists mainly of small round cells 

 with large nuclei, and here the growth assumes the character 

 of a sarcoma consisting of small round cells. The cells are 



