EXPLANATION OF THE PLATES. 



Plate I. 



Fig. 1, a, h. Astemma fiUformix. a. Nat. size. h. Portion magni- 

 fied. 



Fig. 2, a, h. Convoluta paradoxn, magnified, b. Showing the in- 

 vohate margin. 



Fig. 3. PJanaria Jiirudo, magnified. 



Figs. 4-6. Pontobdella littoralis. 4. Nat. size. 5. Magnified. 6. An 

 outline figure drawn from an individual \vhieh had the genital 

 organs extruded. 



Plate II. a. 



Figs. 1, 1*. Omatoplea (jraciJls. 1. Nat. size. 1*. Anterior portion 

 magnified. 



Figs. 2, 2*, 2**, 3, 3*. Omatoplea rosea. 2. Nat. size, both figures. 

 2*. Anterior portion. 2**. Caudal extremity :— both magnified. 

 3. Var. hrunnea, nat. size. 3*. Head magnified. 



Fig. 4. Tetrastemma varicolor, nat. size. 



Figs. 5, 5*. Omatoplea melanocepliala. 5. Nat. size. 5*. Mag- 

 nified. 



Figs. 6, 6*. Omatoplea pulchra. 6. Nat. size. 6*. Anterior portion 

 magnified. 



Plate II. h. 



Figs. 1, 1*, 1**. BorJusia olivacea. 1, 1, 1. Nat. size. 1*. Ante- 

 rior and middle portions magnified. 1**. Embryo? 



Figs. 2, 2*. Borlasia octomlata. 2. Nat. size. 2*. Anterior portion 

 magnified. 



Figs. 3, 3*. Borlasia ptirpiirea. 3. Nat. size. 3*. Head, anterior 

 portion, middle, and tail, magnified. 



Fig's. 4, 5. Astemma rtififrons. 4. Nat. size. 5. Portion of ante- 

 rior extremity magTiified. 



2a 



