38 



loured; their body appears to be very fragile, especially in the clitel- 

 lar region. In the anterior region the body is cylindrical, its posterior 

 region has a quadrangular shape. 



The tail is pointed. The anal opening has a longitudinal triangular 

 shape and lies dorsally. (PI. II. fig. 19). 



The cephalic lobe extends over a third of the buccal segment. 

 The anterior segments are large; with the fourteenth segment their 

 longitudinal diameter commences to decrease, measuring only two 

 third of the length of the anterior segments. 



The setae are situated at the dorsal and the ventral side, in 

 four couples. In the anterior third portion of the body the setae of 

 each couple are separated by a rather great distance, in the poste- 

 rior region they approach each other closely; in the latter region the 

 dorsal setae are situated at the edges of the dorsal side , the ventral ones 

 at the edges of the ventral side. In front of the clitellum the dis- 

 tance" between the setae of each ventral couple (1 and 2) measures 

 about the half of that between the two ventral couples; the distance 

 between the ventral and dorsal couples (2 and 3) is somewhat larger 

 than that between the ventral ones. The distance between the two 

 dorsal couples is somewhat larger than that between the ventral and 

 dorsal one. The distance between the setae of each dorsal couple (3 

 and 4) is equal to half the distance between the two dorsal couples. 



The setae have the usual shape, like in other Lumbricidae; in the 

 clitellar region they are longer and straighter, measuring 0,35 mm., 

 whereas their ordinary length is 0,28 mm. 



The clitellum is characterized by a folded, crenulated ridge, 1 

 mm. broad, situated laterally, between the ventral and dorsal cou- 

 ples of setae (PI. II. fig. 15). This ridge extends usually over ten seg- 

 ments, from XXIII to XXXII; sometimes it commences already in 

 segment XXII. However the number of segments it occupies is not 

 constant, varying from six or seven to fourteen; no doubt this de- 

 pends on the state of sexual maturity of the worms , for in some spe- 

 cimens there is no trace of the ridge at all. The clitellum consists 

 of glandular elements of about the same nature as in Lumbricus, viz. 

 long, tubular cells containing a coarsely granular substance, deeply 

 stained by alum carmine („glandes à gros corpuscules" de Cerfontaine) 

 and elongated , clubshaped cells , containing a finely granular substance , 

 verv slightly stained, except in its basal portion, within which the 



