W. H. Leigii-Sharpe 
291 
NOTE. 
Calliobdella lophii. 
I have to note a specimen of a leech parasitic on Lophius piscatorius sent to me 
by Dr Bowman, having been captured by him on 29. xi. 1910 in the Firth of Forth. 
This I had no difficulty in recognising as Calliobdella lophii, making a further record 
of this animal’s appearance, and on the same host. 
ERRATUM. 
It is agreed, universally I think, that the number of segments in leeches is 34. 
The reasons for this belief I stated briefly in Parasitology, vn, p. 208. 
Accordingly in my article on Ganymedebdella cratere (Parasitology, vm, p. 5, line 
26), “37 segments” should read “34 segments.’’'’ The apparent miscount is due 
to the divergence of opinion as to the way in which annuli are plotted out in segmenta¬ 
tion, it being intended that one of the groups of segments marked with a query 
should not be considered as segments according to whichever view the reader 
favours. I am of the belief that in both leeches described in Parasitology (vn, p. 206 
and vm, p. 4) the three small annuli a, A, b, are the ones that will be proved not to 
be segments in themselves; and subtracting these three from the total, we have the 
correct number 34. 
Dr J. H. Ashworth kindly informs me that Ganymedes is a name pre-occupied 
for a Gregarine (vide J. S. Huxley (1910), Quart. Journ. Micr. Sci. lv, 155), so that 
the alternative name of Ganymedebdella proposed by me ( Parasitology, vm, p. 1) 
will have in future to be used. 
APPENDIX. 
Key to the ICHTHYOBDELLIDAE. 
* typically Northern forms (British waters), 
f typically Southern forms (Mediterranean). 
t* typically Southern forms but examples have been found in British waters. 
X fresh-water. 
Jl some species fresh-water. 
Order. RHYNCHOBDELLIDA (RHYNCHOBDELLAE). 
Leeches with an exsertile proboscis, without jaws, and with colourless blood. 
Family. ICHTHYOBDELLIDAE. 
Leeches whose bodies are divided by a more or less marked constriction into a “ Neck ” 
(Clitellum and Preclitellum) and a “ Body" or Abdomen. The anterior sucker (as well 
as the posterior) is a permanent adhesive organ distinct from the body. Eggs included 
in chitinous capsules which are attached to foreign bodies. 
Tribe I. BRANCHIOBDELLINAE. (Leeches with external respiratory organs. 
Neck very distinctly marked off from the abdomen by a constriction.) 
