ATLAS OF BIOLOGY. 



f.i. Internal aperture of segmental organ. 



sli. Integumentary sheath of seta. 



sh'. Cuticular sheath of seta. 



s.l. Lateral setae. 



KIII. Semitic constriction. 



.n. Muscular sheath of nervous system. 



*.'. Tubular fibres of the same. 



*p. Sperinathecse. 



up'. Apertures of the same. 



s.s. Sac of setee. 



t.v. Ventral setw. 



lj>. 

 ts. 

 v.d. 

 v.d'. 



v.d". 

 v.d'". 

 v.s. 

 zn. 



Typhlobole. 



Testis. 



Vas deferens. 



Internal aperture (mouth or ciliated rosette) 



of the same. 



External aperture of the same. 

 Coiled loop of the same. 

 VesiculiB seminales. 

 Zonitic constrictions. 



1. to 86. Body segments 1 to 30. 



