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Show 1903.] OLIGOCH^TA FROM NEW ZEALAND. 203 generosity in thus affording me an opportunity, for many years to come likely to remain unique, of examining the deep-water Oligochaeta of our lakes. In view of the extremely interesting character of the terrestrial Oligochaates of N e w Zealand, both from a morphological and a zoo-geographical aspect, it seemed probable that our deep lakes of the South Island would contain equally interesting species; but the result of m y investigation, though not wholly without interest, is rather disappointing. For, whereas our terrestrial fauna includes several endemic genera, like Maoridrilus, Plagio-chceta, Neodrilus, Deinodrilus, and Octochcetus, our lacustrine genera are, with one exception, of an exotic character; and even the single new genus that I have ventured to create, viz. Taupodrilus, is very near akin to a European worm, Branchiura coccinea of Vejdovsky. But amongst the new species that are here enumerated, some are of considerable interest. Of the genus Phreodrilus Beddard, originally founded for a New-Zealand worm, but now extended to include certain South-American aquatic species previously placed by Beddard in the genus Hesperodrilus, I find two new representatives: one of which is " Hesperodrilid" in the nature of the male efferent apparatus, and therein agreeing with the Kerguelen- Island form and South-American species, rather than with the original representative from N e w Zealand. This genus thus has a distribution similar to that of our earthworms belonging to the genus Notiodrilus. Two other species deserve mention here : Biporochceta aquatica, sp. n., and Plutellus lacustris, sp. n., for both of these genera are characteristically Australian. The genus Biporochceta was founded originally by Beddard for D. intermedia from Lake Brunner in this colony ; but it has now been extended so as to include a number of Australian species, and hitherto Beddard's species has been the only representative on this island. It is worth noting that both our species occur in water, whereas the majority of the species are terrestrial. As to Plutellus lacustris, it differs from the rest of the species in certain characters, viz., the loss of gizzard, and the absence of nephridia in the pregenital segments ; and at first I was inclined to form a new genus for it, but these features, in which it approaches Pontoclrilus (an inhabitant of the sea-shore in various parts of the world), appear correlated with an aquatic habit. These two genera, Biporochceta and Plutellus, belong to the subfamily Megascolecinaa, and they are the only representatives of this subfamily in N e w Zealand. It is true that Schmarda attributed Notoscolex {Hypogceoii) orthostichon to N e w Zealand, but this appears to have been due to an error-to a lapsus calami. H e gives as the locality " Mt. Wellington " : now, there is no such mountain in the district visited by Schmarda in N e w Zealand, but he did visit Mt. Wellington at Hobart, Tasmania; and there is no doubt in m y mind that he obtained " H. orthostichon" in |