448 WILHELM MICHAELSEN. 



Fam. LUMBRICID^. 



Helodrilns ( Allolobopliora) caliginosus {Sav.) 

 f. trapezoides [Dug.). 



Helodrilns ( Allolobophora) caliginosus trapezoides (Dug.}; 

 Michaelsen, '• Oligochseta," Tierreicli, x, p. 483. 1900. 



Hab. — Howick, Natal ; in detritus near the foot of the 

 Umgeni Falls, W. Michaelsen, August 30th, 1911. 

 A peregrine species imported by man. 



Helodrilns (Bimastus) constrictus [Ro.sa). 



Helodrilns (Bimastiis) constrictus (Eosa) ; Michaelsen, " Oligo- 

 cha^ta," Tierreicli, x. p. 503. 1900. 



Hab. — Howick, Natal; in detritus neiir the foot of the 

 Umgeni Falls, W. Michaelsen, August 30th, 1911. 

 A peregrine species imported by man. 



ANALYTICAL KEYS TO THE OLIGOCHiETA FEOM 

 NATAL AND ZULULAND. 



A. KKY FOUNDED CHIEFLY ON EXTERNAL CHAEACTEES. 



1 ('. Minute white or dirty grey worms not longer than 20 mm., 

 less than 1 mm. thick. Male papillae on the twelfth 

 segment. Clitellum at the twelfth segment and the 

 immediately adjoining parts of the eleventh and 

 thirteenth segments. .... 2 



1 b. Larger worms, at least 20 mm. long and thicker than 1 mm. 



Male papilke further hack than the twelfth segment. 

 Clitellum occupies at least three complete segments 

 including the sixteenth segment, if not beginning 

 further back. ..... 3 



2 a. Constantly two setse in a bundle. 



Fridericia peregrinabunda n. sp. 

 2 b. More than two seise in a bundle, viz. 4-6, the middle ones 

 being smaller than tlie outer ones. 



Fridericia per rieri (Vejd.) 



