418 



ZOOLOGY 





of the ground or in the interior of its burrow. The setae in the 

 clitellum, and those in the neighbourhood of the genital apertures, 

 are much slenderer than the rest. Along the middle line of the 

 dorsal surface, from about the eleventh segment backwards, is a 

 row of small apertures, one at the line of division between each 

 contiguous pair of segments : these, which are termed the dorsal 

 pores, perforate the body-wall and open internally into the ccelome. 

 On the ventral surface are two rows of minute apertures a "pair 



B 



-'*. Lumbricus agriCOla. A, entire specimen, lateral view ; , ventral view of anterior 

 portion -if the body, magnified. 1, la, 33, first, fifteenth, and thirty-third segment*. Tlu- 



r Yogt 



on each segment the < On 



,'iiiral sumce of the fifteenth segment (Fig. 328, 15), is 



pair of slit-liko. -apertures with somewhat tumid lips, the 



reprodi res; and on the segment immediately in front, 



the fourteenth, are two smaller rounded apertures, the fcinl< 



Ir the intervals bf-t\\een the ninth and 



tenth, and tenth and eleventh segments are two pairs of small 

 3, the openings of thr 



