OLIGOCH^STA 311 



3. BOTHRIONETTRTJM Stole. Forked setae alone present; ventral 

 setae of segment 11 modified for copulatory purposes: several species. 



B. glaber Moore. Body pinkish or brown, 4 cm. long- and .8 mm. 

 wide; setae short and forked at the end: Vineyard Sound, under decay- 

 ing vegetation and stones near high-water mark, especially where the 

 water is brackish. 



4. LIMNODRILUS Claparede. Forked setae alone present; contrac- 

 tile hearts in segment 8 and 9 ; blood capillaries penetrate the body wall ; 

 prostate gland large and massive, in segment 11: about 10 species, in 

 fresh water. 



L. claparedianus Ratzel. Length 4 to 7 cm.; segments 150: eastern 

 states, in fresh water. 



L. subsalsus Moore. Body red or brown in color and 4 cm. long; 

 segments 120; setae deeply bifid, 4 to 6 being in each group before and 

 2 to 4 behind the clitellum : in brackish water at New Bedford, Mass. 



FAMILY 7. LUMBRICULIDAE. 



Small worms usually red or brown in color, living in mud in fresh 

 water; 2 pairs of dorsal and 2 of ventral setae in each segment; 2 pairs 

 of sperm ducts, but with 1 pair of openings: 8 genera and about 15 

 species. 



1. TRICHODRILTTS Claparede (Tliinodrilus Smith). Setae simple or 

 forked at the end; dorsal blood vessel with paired contractile, blind 

 appendages ; male pores in segment 10 : 3 species. 



T. inconstans (Smith). Length 6 cm.; width 8 mm.; color reddish, 

 a nteriorly greenish ; 5 pairs of small spermathecae : in mud or vegetation 

 in fresh water. 



FAMILY 8. MEGASCOLICIDAE. 



Usually terrestrial, sometimes aquatic oligochasts; setae curved, 8, 

 12, or more on a segment; male pores on segment 18 or 17; clitellum 

 beginning on or before segment 16, not appearing excepting at certain 

 times and without sharp boundaries: 56 genera and about 600 species, 

 principally in the southern hemisphere and the tropical portions of the 

 northern. 



1. DIPLOCARDIA Garman. Setae paired, 8 on a segment, absent on 

 segment 18; clitellum on segment 13 to 18: about 10 species, all 

 American. 



D. communis* Gar. Length 30 cm.; diameter 3 mm.; flesh-colored; 

 dorsal vessel double ; 3 pairs of spermathecae in segments 7 to 9 : in the 

 soil of the prairies (Illinois). 



* See "On the Anatomy and Histology of a New Earthworm (Diplocardia com' 

 munis)," by*H. Garman, Bull, of 111. St. Lab. of Nat. Hist.. Vol. 3, p. 47, 1892. 



