42 (JfO) Setae distinctly sigmoid 43 



42 (40) Setae straight or curved at one end 44 



43 (45) Setae with a distinct node (Fig. 74). Twenty- 

 six to 28 segments Cernosvitoviella immota 



Figure 74. — Seta. 



43 (42) Setae without a node (Fig. 75). Thirty-eight 



to 42 segments Lumbricilbis lineatus 



Figure 75. — Seta. 



44 {Jt2) Setae straight (Fig. 76). Setal bundle fan-shaped, with 

 setae decreasing in size towards center of bundle (Fig. 77) . 

 Gut diverticulae present in segment VIII (best seen in 



living material). Thirty-nine to 50 segments 



Henlea ventriculosa 



Figure 76 (left).— Seta. 



Figure 77 (right). — One setal bundle. 



44 (45) Setae curved distally (Fig. 78). Setal bundles not 

 of above form. No gut diverticulae. Twenty seven 

 to 30 segments Marionina spicula 



Figure 78. — Seta. 



^ 



45 (5) Mature worms up to 72 mm long, 3 mm diameter. Small 

 spermathecal pores located in line with, or slightly lateral 

 to, the lateralmost setae of the ventral bundles (Fig. 79). 

 Dorsal setae in posterior segments in regular ranks (Fig. 

 80). Transverse genital marking present on ventral sur- 

 face between segments XIX and XX. Pontodrilus bermudensis 



Figure 79 (top). — Ventral view of segments VII to IX; A, B, 

 lines of ventral setae; B, lateralmost; L, seta; S, sperma- 

 thecal pores. 



Figure 80 (bottom). — Dorsal view of some posterior segments; 

 C, D, lines of dorsal setae; E, seta. 



17 



