Via. 256.— Dissection of II„h,lImria tnhulosn. x i. ]. FeL-leis ; 2, feeler-ampullae ; S, 

 ring-canal ; 4, Polian vesiclf ; o, stoiie-oanals ; 6, radial canal ; 7. nne of a jiair of 

 longitudinal muscles; 8, genital tubes; 9, intestine; ]0, radiating muscles of 

 cloaca; 11, base of respiratory tree ; 12, ventral Mood-vessel ; 13, plexus of dorsal 

 blood-vessel. (After Ludwig.) 



