B 



nfi.it 



FIG. 117. Hirudo medicinalis. A, dorsal; B, ventral aspect, a, anus; a. s, 

 anterior sucker; e. I. first pair of eyes; e. 5, fifth pair; gp. rf , male gonopore; 

 gp. $, female gonopore; ith, mouth; /. /, first pair of nephridiopores; 

 np. 77, seventeenth pair; /. s, posterior sucker; s.p, sensory papillae; I-XXVI, 

 segments. (Partly after Whitman.) 



20 4 



