232 



METAZOAN PHYLA 



Prosfomi'um 

 Moufh 

 A/erves 

 Buccal cav/^y 



Supraphcrry/^^^eal 

 Pharynx 



Hearts 



Fsophagfecf/ 

 pouch 



Ca/c/ferous 

 g/ar7c/s 



Esophoigfus 

 Crop 



Gizzorrcf 



In-tesf/'ne 



Dorsa/ b/ooo/ 

 vesse/ 



Fig. 136. — Diagrammatic representation of the anterior part of the alimentary canal 

 of an earthworm. Based upon a preserved specimen. The blood vessels are shown in 

 solid black. Segments numbered in roman. 



-Nephrostome ^^Nephn'di'opore 

 /rter5egn7ef^ta/ 



Collecfm^f 

 regt/on 



Fig. 137. — Diagrammatic view of the nephridium of an earthworm. In the body this 

 is invested with soft connective tissue and the loops of the tubule are crowded together. 

 Highly magnified. 



