144 The British Leeches 
Albione verrucata , Savigny, 1822, p. Ill ; Moquin-Tandon, 1826, p. 137, pi. vii, 
fig. 5. 
Sipunculus marinus , De Serres, 1822, p. 61. 
Sanguisuga muricata, Bruguihre, 1824, p. 133, pi. lii, fig. 5. 
Albione areolata, Moquin-Tandon, 1826, p. 138. 
Pontobdella laevis, de Blainville, 1827, p. 243 ; de Blainville, 1828, p. 557, pi. xxxiv, 
fig. 3; Moquin-Tandon, 1846, p. 290; Thompson, 1846, p. 391 (recorded from 
Ireland); Diesing, 1850, p. 439 ; Grube, 1851, p. 108 ; Thompson, 1856, p. 427. 
Pontobdella verrucosa, Leydig, 1851, p. 318, pi. ix, fig. 2 (anatomy). 
Diagnosis. Body cylindrical, fusiform, much attenuated anteriorly, 
grayish green or brownish green, somewhat lighter on the ventral 
surface, with irregular dark brown spots. Anterior sucker with six 
small marginal papillae. 
The anterior sucker includes the first four somites. Somites V, 
VI, X, XI, XII and XXIV—XXVII biannulate, VII, VIII and IX 
triannulate; the eleven somites XIII—XXIII following the clitellum, 
are complete with four rings. The first ring of the complete somite 
is the largest, the third is the smallest, the second and fourth are of 
equal length. The papillae in each somite are disposed upon their 
several rings according to a definite and characteristic pattern which 
however may become modified to a certain extent when, as not 
infrequently happens, some papillae are missing or extra ones are 
intercalated. The typical arrangement on the dorsal surface is in¬ 
dicated in Text Fig. 3 (p. 147). The largest papillae occur on the first 
ring of the somite and are eight in number, and there are usually ten 
upon the second and twelve upon the fourth ring. 
The papillae may be prominent, conical and terminated by an array 
of spiny tubercles forming a kind of rosette [the typical form], less 
acute, mammiform and without the terminal rosettes [P. verrucata], 
so far sunk into the body as to leave an irregular basal marking [P. 
areolata] or entirely retracted, leaving the surface smooth [P. laevis]. 
The clitellum extends from the second and last ring of somite X 
up to and including the last ring of somite XII. ■ 
The male genital orifice lies between the two rings of somite XI, 
that is, between the 16th and 17th rings following the anterior sucker. 
The female orifice is situated two rings behind the male, between the 
first and second rings of somite XII. 
The anus lies upon the first ring or between the two rings of somite 
XXVI. The crop has a single undivided caecum reflected posteriorly. 
Length, at rest, 75—100 mm.; fully extended, up to 200 mm. 
Width 8—15 mm. 
