W. H. Lbigh-Siiarpe 
207 
of Calliobdella with the 3rd and 4th of Pontobdella, and the 4th of 
Calliobdella with the 5th and 6th of Pontobdella. 
Judging from my specimens, the diagnosis is as follows, which is 
made plain on reference to Fig. 1 : 
(a) Nech. A. Head : 
5 or 6 segments. 
(a) Anterior Sucker : which shows annulations which gradually 
fade away and grow more indistinct anteriorly. 
{b) 3 small annuli each of which is a complete segment. 
Total 9 (or 8) segments. 
B. Preclitellum : 
11 annuli, all more or less divided by chorisis (except the first 3 
or 4), in many cases the division not extending right across the annulus, 
so that the number of subdivisions of the annulus does not always 
appear to be the same on both sides of the specimen. The whole of 
the 11 annuli only represents 3 segments. The preclitellum is divided 
from the clitellum by a deep furrow which shows as a very marked 
line in a preparation cleared in creosote, viewed under the microscope 
as a transparent object. 
C. Clitellum : 3 segments. 
The first two segments are very large and not divided into annuli 
by furrows, though the edges of the animal, viewed as a flat object, 
show indications of subdivisions. The male genital aperture is between 
these two segments or somewhat towards the anterior border of the 
second. It is this segment that bears the orange band. The third 
segment is small, and is divided into six minute annuli which are not 
again divided. 
The female genital aperture is between the second and third segments. 
I do not find any lateral tubercles on the neck whether respiratory 
or otherwise. 
{S) Body or Abdomen. (A) Testis Eegion and Caecum Region 
TAKEN TOGETHER. 12 segments. 
Each of the 12 segments is completely divided into 6 annuli. 
The first 11 only, of these 12, bear lateral respiratory vesicles one on 
either side of each segment, bordering the first two annuli of these 
