56 SCOLOCES. 



2. Enchytraeus. Setae quadriserial, 3-4 in a fascicle : blood colour- 



less. 



3. Saenuris. Setse quadriserial, 3-9 in a fascicle : blood red. 



Family II. LITTOKELES. Littoreal, burrowing in wet mud mixed 

 with sand. 



4. Clitellio. Setae quadriserial, fasciculate: the body with a white 



clitellus. 



5. Valla. Segments armed with setaceous bristles in four fasciculate 



series ; the 1 0th segment with strong spines. 



Tribe II. Naidina. 



Head distinct from the body, the first three or four segments 

 without bristles. 



Family III. NAIDES. The only family. 



* The four front segments without superior setce. 



6. Proto. Anal extremity with digitiform (branchial?) appen- 



dages. 



7. Stylaria. Oral extremity produced into a style. 



8. Serpentina. Ophiocephalous : anal extremity naked. 



9. Nais. Head continuous with the body : oral extremity truncate, 



the anal rounded, obtuse. 



** All the segments without superior setce. 



10. Chaetogaster. 



