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Show 1 9 0 4 . ] EARTHWORMS FROM NEW ZEALAND. 2 5 7 and if such a duct exists in Ar. orthostichon, it seems unlikely that it would have escaped Beddard's notice. Moreover, in T. maorica the chsetal formula is different, whereas in T. kirki it is similar to that of JV. orthostichon, and the spermatheca is without a distinct muscular duct. The only other characters are the extent of the clitellum and its size. Beddard gives the former as occupying segments 14 to 17 inclusive, whereas in my species it begins at segment 13; and as to size, Schmarda gives it as 80 cm. x 4 cm., with 60 segments- distinctly smaller than T. kirki, though approximately that of T. maorica. It appears, then, to be distinct from either of the two species possessing only two pairs of spermathecse; for, apart from any similarities, the prostate in those two species is of considerable length. But it agrees more closely with T. huttoni, in size, in chfetal formula, extent of clitellum, and small size of prostate; but in that species there are three pairs of spermathecse. So far, then, as our information allows us to judge, Schmarda's species is distinct from any of those described in the present paper; and we have not sufficient information to allow us to say definitely that it even belongs to the genus Tokea, although it appears not improbable that it does so ; but Beddard states that the sperm-sacs number three pairs, and occupy segments 10, 11, 12-an unusual arrangement, even in Notoscolex, where 11, 12 is the more general position. Remarks on the Genera Megascolides and Notoscolex. It is very evident that this new genus Tokea is nearly allied to the Cryptodriline genera Megascolides and Notoscolex; but it appears to me to differ in details from either of them. It is notoriously difficult to define these Australian genera; and it is unfortunate that the opinions of our two leading systematists, Beddard and Michaelsen, are absolutely at variance as to the characters and limitations of the genus Megascolides. This name was given by Prof. M‘Coy in 1878 to a worm, M. australis, which, at a later period, received full anatomical treatment at the hands of Baldwin Spencer (1888); and this it is which Michaelsen (1900) takes as the type of the genus, of which he gives this diagnosis (p. 182, translation): " Eight chaste ; clitellum beginning at or before segment 14 and extending over 6 to 977 segments. One pair of female pores; spermathecal pores 2 to 5 pairs, the last being on 8/9. Gizzard 5 or 6, or 5 and 6. Excretory organs consist of diffuse nephridia, to which is added a pair of meganephridia in each of the posterior segments. Prostate tubular (sometimes lobate)." (Italics are Michaelsen's.) It will be seen, then, that in some of the above characters the new genus agrees with Megascolides, and notably in the coexistence, in the hinder segments, of meganephridia with micro- P roc. Z ool. Soc.- 1904, V ol. II. No. XVII. 17 |