450 



ZOOLOGY 



SECT. 



arranged in two rows ; in the latter (the terminal vesicle) the 

 passage is lined by cells, and is thus intercellular, and there is a 

 thick muscular investment. The nephridia are abundantly supplied 

 with blood by means of nephridial branches of the ventral vessel. 



//tes 



coe 



exl 



.'/.- f .: 



J[ 



Fid. 308. Nepliridiumof Lumbricus (diagrammatic). a. ampulla between ciliated aiul non- 

 ciliated parts of the intracellular canal ; oil. ciliated part of the intracellular canal ; coe. 

 investment derived from the coelomic epithelium ; cxt. nephridiopore ; Ic. non-ciliated part 

 of the intracellular canal ; mes. septum ; nst. ncphrostome ; t.v. intercellular canal of the 

 terminal vesicle. /. ///. the three principal loops. (From Meisenheimer, after Maxiarski.) 



Reproductive Organs. The Earthworm is hermaphrodite. 

 There are two pairs of very small flattened testes (Figs. 366, 369, te, 



