82 W. HAROLD LEIGH-SHARPE. 



with minute black dots ; the body is of a clear brownish green, orna- 

 mented above with broken, parallel black lines. The body is paler 

 miderneath, showing rose-pink markings in the form of a V. It is very 

 noticeable also that the last segment but one of the neck is ornamented 

 with an orange band which encircles it. The movements of this leech 

 are very lively." 



They were very lively in captivity, clinging firmly with the posterior 

 sucker to the jar containing them, and seeking eagerly for some fresh 

 host with the anterior end. 



They moved occasionally with the usual loop-like movements of a 

 leech, taking great care to place the posterior sucker as exactly as possible 

 in the position previously occupied by the anterior. 



Calliobdella is sharply divided by a constriction into a neck and a 

 body. Blanchard,* who mentions this leech as occurring in the Mediter- 

 ranean, states that the segments of the body are formed of three to six 

 annuli according as the three primordial rings are more or less divided 

 by chorisis. All those in my possession have six annuli to the segment. 

 The same author suggests that the animal is flattened when young and 

 rounded when old. Further, he alters the name for orthographical reasons 

 to Callobdella. 



On the body, but not on the neck, are lateral protuberances, eleven 

 pairs of hemispherical projections on each side of the animal, "rising 

 and falling as if by respiration," as Dalyellf said of a leech he described 

 as " Hirudo vittata," and which possibly was the same. These are rudi- 

 mentary branchiae, corresponding to the large external branchiae of 

 Branchellion, and similar to those of the North American and European 

 marine and fresh- water form, Cystibranchus. 



According to QuatrefagesJ these appendages do not receive the blood 

 contained in the vessels, but only the lymph which becomes diffused,, 

 and which makes the respiration truly lymphatic. 



Ichthyobdella is without these tubercles, and Pontobdella, which is 

 further distinguished by its warty appearance also. Owing to the six 

 annuli of the segment being formed by chorisis from three, the first 

 respiratory vesicle is on the first double ring, the second on the fourth 

 double ring, and so on. The anterior half of each double ring carrying 

 the vesicle is spotted. 

 There are no eyes. 

 The extreme size of the posterior sucker in C. lofhii, it being 



* " Hinidinees de I'ltalie, Boll. Mus. Zool. Torino," Vol. IX, 1894, No. 192. 

 t "Powersof the Creator." Dalyell. Vol. II, p. 9, 1858. 

 X Ann. Sc. Nat., Vol. XVIII, p. 322, 1852. 



