44 



CLASSIFICATION OF THE ANIMAL KINGDOM. 



CLASS II. ANNELIDA (Ringed Worms). 

 OKDER I. HIRUDINEA (DISCOPHORA, LEECHES). 



Fam. a. Malacobdellidse. Malacdbdella. 

 Tarn. &. Acanthobdellidse. Acanthobdella. 

 Fam. c. Branchiobdellidse. Branchiobdella. 

 Fam. d. Clepsinidse. Clepsine, Piscicola (fig. 39). 

 Fam. e. Hirudinidse. Sangwsuga (HirwLo), Trochetia, 

 Nephelis (fig. 39), Hcemopsis, Pontobdella (fig. 39). 



Fig. 39. Hirudinea. A, Semi-diagrammatic view of Piscicola geometrica, enlarged : a, The 

 anterior, and p, the posterior sucker ; g, The pharynx, with the proboscis; c, The proven- 

 triculus ; s, The proper stomach ; o, Sphincter separating the stomach from the intestine ; 

 i, Intestine, with lateral cssca ; r, Rectum, terminating in the aperture of the anus. B, Pon- 

 tobdella muricata, of the natural size : a, Anterior, and p, posterior sucker, c, Nephelis 

 octoculato:, viewed from above, of the natural size : I, Upper lip, carrying the eye-spots ; c, 

 Posterior sucker. D, Cocoon of the preceding, with eggs, enlarged. E, An older cocoon of 

 the same, with young leeches, enlarged. (After Leydig and Moquin-Tandon.) 



