SEA-FISHERIES LABORATORY. 121 



about one-tenth of this in length, with a very fine con- 

 nective tissue stroma, disintegrated cell fragments, and 

 apparently loose melanin granules make up the general 

 mass of the tumour. 



In some parts of the tumour, and after successful 

 staining with methyl-blue-eosin, there are generally 

 distributed masses of " eosinophilous " cells, or numbers 

 of such cells lying singly among the surrounding 

 melanotic and connective tissue elements. Some of 

 these are represented in fig. 3, PL II. They stain bright 

 red, and stand out clearly from the other cells containing 

 melanin. As a rule, their nuclei are not very easily 

 seen — the defect of the staining method, for treatment 

 with haematoxylin and eosin shows the nuclei clearly, 

 though the general distribution of the cells themselves 

 is not then so obvious. It is noticeable that many of 

 these brightly staining cells appear to be situated in 

 cavities, and to lie loosely with no obvious relation to the 

 stroma. For the most part they are either modified or 

 unmodified red blood corpuscles, and their general 

 distribution is due to the breakdown of the walls of the 

 capillaries and smaller arteries and veins. Fig. 3 thus 

 represents what is apparently a large capillary, or small 

 vessel, with an incomplete wall. Sarcomatous cells, 

 containing melanin, surround this wall, and it would 

 even appear that some of these cells adhere to it. Not 

 all the eosinophilous cells, however, are blood corpuscles, 

 some of them appear to be leucocytic in nature, and some 

 have deposits of melanin. This infiltration of the sarco- 

 matous tissue by migrant cells, or blood corpuscles, can 

 be traced in most parts of the tumour; in fig. 1, for 

 instance, a red blood corpuscle is shown. 



The growth is, therefore, a melanotic, mixed-cell 

 sarcoma, showing a general tendency on the part of the 



