ZooL.— Vol. II.] EISEN—OLIGOCHMTA. II 7 



External Characters. 



Somites. — They increase slightly in size towards XI; 

 XII and XIII are smaller, and XIII is smaller than XII ; 

 XIV is larger and from it the clitellar somites slightly 

 increase in size towards XIX; XX is smaller. 



The prostomium slightly divides somite I. It is furnished 

 with a deep transverse groove in line with the upper margin 

 of somite I. 



The clitelhim extends from the anterior 1/3 XIII-1/2 XX. 

 It is equally developed on dorsal and ventral sides. 



Male -pores are situated on two small round papillae in 

 XVII, not connected by any special zone. In each papilla 

 is seen a sac-like lumen, into which open the sperm-duct 

 and the prostate, which thus unite but do not fuse just 

 before reaching the exterior. Both setas a and b are pres- 

 ent at the male papilla, setee a being situated on the side of 

 the papilla. 



Internal Characters. 



Genital Zone. — There are no tubercula pubertatis like 

 those found in Lumbricidas; but I find in the posterior part 

 of somite XV and in the anterior part of XVII, as well as 

 in XVIII, a zone in which the glandular cells of the clitellum 

 are absent. Instead of these we find here a continuous 

 row (in longitudinal sections) of very short and broad 

 epithelial cells, characterized by having their frayed distal 

 ends terminating in a number of long and pointed processes. 

 Some of them project beyond the muscular layers and can 

 even be followed to a point where I think they connect with 

 the ventral ganglion. 



The long tubular glands of the clitellum end at the begin- 

 ning of the genital zone, though the long narrow ducts of 

 many of these cells are seen to bend inwardly and pass 

 through the zone. The zone possesses a stratum of longi- 

 tudinally arranged glands running parallel to the body-wall, 

 in somewhat the same manner as the spermathecal setae- 

 glands of Diplocardia Udei. None of these glands open 



