SEA-FISHERIES LABORATORY. Pore is 
aspect, certainly such as to prejudice a buyer against it, 
though it could have had no evil effect on the health of 
anyone using the fish as food. 
IIf. Melanotic Mixed-Cell Sarcoma. 
This is by far the most interesting of the three 
tumours. It was found by Professor Herdman in a Ray 
(fava clavata) caught in the trammel net of the Biological 
Station, in Port Erin Bay, in August, 1910. From the 
general appearance of the fish Dr. H. E. Roaf expressed 
the opinion (since fully confirmed on examination of the 
specimen) that the growth was a melanotic sarcoma. The 
head of the Ray was preserved in formalin, and small 
pieces from the tumour and various organs were preserved 
by Mr. Chadwick in Zenker’s fluid. Except for the 
deposition of mercury compounds in the tissues, due to 
imperfect washing out of the fixative, the preservative is 
all that can be desired. I am obliged to Dr. E. Glynn, of 
the Pathological Department at the University, for con- 
firmation of the diagnosis of the nature of the tumour. 
The Ray was evidently greatly emaciated—so much 
so, says Mr. Chadwick, ‘‘ that the outlines of the skeleton 
could be distinctly seen when the fish was alive.’? On the 
right side of the head (see the photograph, Pl. III) 
between the eye and the margin of the body, but quite 
close to the latter, was a tumour, elliptical in outline; 
measuring 75 by 60 mm.; and raised up above the level 
of the skin by about 15 to 20mm. The growth was dense 
black in colour, but at the edges the pigment faded away 
gradually into the normal grey colour of the skin. The 
whole growth was evidently covered by epidermis, or by 
a modified, infiltrated epidermis. The tumour was injured 
by the removal of the fish from the net, so that it is much 
broken in the central parts, but not so much so as to 
