SEA-FISHERIES LABORATORY. 109 
it aside.* The host was a ‘‘a very large Ray.’’+ The 
leech is 26 cms. in length, and about 1:8 cms. in diameter 
at its thickest part, which is just in front of the oral 
sucker. The skin is quite smooth, green in colour{ (after 
preservation in formalin), with no trace of clitellus. The 
segments are obscurely marked. The oral sucker is rather 
smaller than the anal one. The body is thinnest near the 
head, and increases gradually in diameter to near the 
anus. 
(4) VaRrIoUS PATHOLOGICAL CONDITIONS. 
Three examples of fish tumours were sent to me during 
the last year, and may be worth describing. 
I. Hard Fibroma. 
In July, Mr. N. M. Richards, a member of the 
Cornwall Sea Fisheries Committee, sent me a pilchard 
with a tumour projecting from the alimentary canal. 
Apparently the condition, though rare, is not unique, for 
the sender had already seen ‘‘one or two’’ similarly 
affected fishes. The specimen was not in very good condi- 
tion when it arrived, for the tumour had ruptured the 
abdominal wall, and the whole alimentary canal had 
‘‘ gone adrift.”’ Fig. 6, which represents the part of the 
fish containing the growth, and is reproduced one-half the 
natural size, is, therefore, to some extent a “‘ restoration,”’ 
but is sufficiently accurate. 
The tumour was attached to the alimentary canal just 
at the origin of the caecum, and its capsule is continuous 
*Mr. Bailey has sent me further specimens recently. The hosts 
were Raia clavata, caught south-west from Ireland, off Tory 
Island, and off the coast of Morocco. 
+ Probably R. clavata. If it had been a R. batis the man would Have 
called it a ‘‘ Dunn.” 
t One specimen, obtained lately, has coloured the spirit in which it 
was preserved yellow-green. 
