192 ANNULATAL. 
Fig. 118.—Fikxst DissecrIOoN oF Fig. 119.—SEconp DIssECTION 
Lreecu (Hirudo). or LEECH (47rudo). 
(Ad nat.) (Ad nat.) 
Brain. 
2 
ae th 
3 » 
we S 
au : 
tp 
(Esopha 
Crop with eleven pairs of pouches. 
Nephridia. 
a — 
[s] 
5 g 
é ES 
. 2 ag 
od 3 a= 
5 cc 2m 
3 - 33 
a 
ae Ag 
a ne 
oH ew 
is > 
oe 
Ds 
Sa 
‘Ed 
Z 
fo} 
a 
The body-wall is cut open along the The alimentary canal is picked out, and 
mid dorsal line and pinned back. the nervous, blood-vascular, genital 
and excretory organs are exposed. 
