JOTTINGS—SACCULINA CARCINI, THOMPSON. 79 
Jottings from my Note-Book. By Davin Roserrson, 
F.LS., F.G.S. 
SACCULINA CARCINI, Thompson. 
[Read 27th December, 1892.] 
This parasite infests the abdomen of the common shore crab 
(Carcinus menas, Linn.), and is very plentiful in Row Bay, in 
12 to 14 fathoms, where the bottom consists of black stinking 
mud. It is also not uncommon in some parts of the adjoining 
Gareloch, in 20 to 23 fathoms. On several occasions, when 
dredging in the yacht Medusa, particularly in Row Bay, a short 
distance above the anchorage of the old training ship, it was usual 
to bring up one or more specimens of C. menas in each haul, and 
nearly every one was infested with the parasite. Captain Turbyne, 
‘of the Medusa, tells me that during several years’ dredging in the 
Firth of Clyde and West of Scotland he has rarely seen the 
parasite unless at the two places referred to. Can it be that the 
foul state of the sea-bottom is favourable to the production of 
_ these parasites? We can scarcely say that these particular localities 
are the special home of the crab. The parasite could not, but the 
crab could, if so inclined, leave the place and go to another more 
’ congenial to its habits. It does not seem, however, to avail itself 
of this power, yet neither the parasite nor the host appears to 
‘suffer from the choice of locality, as both have the appearance of 
_ living under favourable circumstances. It is possible that the 
_ parasite may thrive best on a host which feeds on such unclean 
_ fare as is tobe found in the localities referred to. 
