PART II.— OLIGOCHAETA. 
By Prof. W. Michaelsen. 
Pp. 117 to 232, with Plates I and II, a map, and 34 
diagrammatic figures. 
Introduction. — H itherto not a single species of Oligochaeta 
had been recorded from S.W. Australia, the known members of 
this group being confined almost exclusively to the Eastern 
States, the only species from outside that area previously de- 
scribed being a few from South Australia, one from Central 
Australia, and one from the Ncrth-West. 
Then follows a general description of the Oligochaeta and a 
list of the discoveries in the South-West, which includes 52 species 
belonging to 18 genera, viz. : — 
Family NAIDIDAE. 
Genus Pristina . — 1 known species ; fluviatile ; widely distributed. 
Family TUBIFICIDAE. 
,, Clitellio . — 1 new species ; marine; endemic. 
Family ENCHYTRAEIDAE. 
,, Enchytraeus . — 1 known species; terrestrial and littoral; 
introduced. 
,, Michaelsena . — -2 new species ; marine and fluviatile ; en- 
demic. 
„ Fridericia . — 1 known species ; terrestrial; introduced. 
Family HAPLOTAXf DAE. 
,, Pelodrilus . — 2 new species ; fluviatile; endemic. 
Family MEGASCOLECIDAE. 
Sub-Family Acanthodrilinae. 
,, Eodrilus . — 1 new species ; terrestrial; endemic. 
,, Microscolex . — 2 known species ; terrestrial and littoral ; 
introduced. 
Sub-Family Megascolecinae. 
,, Plutellus . — 11 new species ; terrestrial; endemic. 
,, Pontodnlus . — r new, 1 known species ; littoral; endemic; 
1 sp. widely distributed. 
,, Megascolid.es. — 1 new species ; terrestrial ; endemic. 
„ Woodwardia. — 4 „ ,, 
,, Notoscolex. — 6 ,, 
,, Megascolex . — 11 ,, 
,, Pheretima . — 1 known species ; terrestrial; introduced. 
Family LUMBRICIDAE. 
„ Eiseniella . — 1 known species; terrestrial and fluviatile; 
introduced. 
„ Eisenia . — 1 known species ; terrestrial ; introduced 
„ H elodrilus . — 3 
