AITRUDO, 197 
LEECH. 
SEGMENTS. ence epee ne eae SENSE-ORGANS., | APERTURES. 
Prostomium | Brain Mouth. 
I | Eyes 
2 Sub- nu 2 
3 | ; esophageal “3 
4 mass. " 4 
5 a) 
6 |Ganglion 1 Nephridium1 Sense-organs. 
7 " 2 2 " 
8 " 3 3 W 
9 " 4 4 " 
Io " 5 5 " é ap. 
II " 6 6 Ovisacs. " Q ap. 
12 " 7 7| i Testis. " 
13 " 8 8 2 " u 
14 tt" 9 9| 3 tt " 
15 n Io Io] 4 " " 
16 " Il I1| 5 a a 
17 n I2 I2| 6 " " 
18 u 13 13| 7 " " 
19 " 14 14/8 " " 
20 " 15 I " " 
21 " 16 I 2 " 
22 " 17 17 " 
23 Nn 18 " 
24 " 19 " 
25 " 20 " 
26 " 21 " 
27 " 22 
28 
a Posterior 
3I ganglion 
32 (23) 
33 Anus. 
