W. H. Leigh-Sharpe 
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times the size of the mouth sucker. The circumstauce that C. lopliii, 
a rare leech, has been liitherto exclusively found on a single host, viz. 
Lo'phius piscaforiits, leads one to the assumption that it is a completely 
stationary parasite which never leaves its host. With this are correlated 
the following facts ; (i) in C. lophii the posterior sucker is much more 
powerfully developed than in C. nodulifera, which is known on a dozen 
hosts and has the posterior sucker only double the size of the anterior 
one, so that C. lophii is more adapted to hold fast to the body of the 
host; and (ii) the skin musculature is much more weakly developed in 
C. lophii than in C. nodulifera. Indeed the longitudinal muscle layer 
is so weakly developed in C. lojihii that the animal can hardly swim 
freely. Both suckers are of a creamy-pink “ flesh ” tint, and are 
altogether paler and of a different complexion from the rest of the 
animal. 
Segmentation. The neck consists of 22 annuli, but from the work 
of others I am forced to conclude that this number is not constant in 
the genus. 
Blanchard describes C. lubrica as follows ; 
Neck: 3 small segments, followed by 11 large, more or less divided 
by chorisis, followed by 6 small. 
The 2nd, 5th, 8th and last carry a small non-respiratory tubercle. 
Clitellurn : 2 large and 6 small segments ; the male genital aperture 
being between the first and second, and the oviduct opening between 
the last but one and the last but two (?). 
The abdominal somite is formed of 3 (?) or 6 rings, according as the 
3 primordial rings are more or less divided by chorisis. Tivelve {sic) 
respiratory vesicles, the first on the first double ring, the second on the 
fourth double ring, and so on. The anterior half of each double ring 
carrying the vesicles is marked on the dorsal face with whitish spots. 
After the last pair of vesicles one counts 8 rings of which the 4th and 
7th carry white spots. The anus opens between the last and the last 
but one. 
Compare with this the account given by Johannson (1896) of C. 
lophii : 
“ Each typical segment consists of 4 annuli, which are derived from 
one another by chorisis. The 1st and 2hd of these annuli which are 
broader than the others are often divided into two, so that there come 
to be 6. Often in this genus is every fourth ring distinguished by 
papillae.” 
There is no doubt that there are 6 annuli to an abdominal or body 
