384 NOTES ON AUSTRALIAN EARTHWORMS, 



of the anterior annuli ; after iv for some distance the segments 

 are tri-annulate with the setae on the middle annuli, sometimes a 

 faint indication of four annuli ; behind the girdle the segments 

 are narrower, tri-annulate, or sometimes bi-annulate, or quite 

 posteriorly even smooth. 



Setse with a slight sigmoid flexure, about 0-7 mm. long, with a 

 slight enlargement about J from the free end, the width again 

 increasing slightly a little further back, then diminishing gradually 

 a very little towards the imbedded end ; in eight longitudinal rows 

 forming two pairs, those of each outer pair a little further apart ; 

 the first row on each side about 2 mm. from the median ventral 

 line ; the second row about 1 mm. from the first ; the third about 

 3 mm. from the second ; the fourth about 1-5 mm. from the third ; 

 thus even the outer pairs are scarcely or only just lateral in 

 position. 



Clitellum absent in the smallest specimen ; in the others com- 

 mencing with the posterior annulus of xiii and taking in just 

 the anterior margin or nearly the whole of xviir, complete all 

 round except for the fossa presently to be mentioned ; in one 

 specimen not so thick as to obscure the setfe and annular and 

 intersegmental grooves, but in two other cases so tliick as com- 

 pletely to do so. The ventral surface of segments xviii to xxi 

 is thickened and flattened ; and immediately behind the junction 

 of XVII and xviil but on the anterior annulus of xviil and within 

 the limits of the clitellum in two of them is a long narrow shallow 

 depression or fossa, 8 or 9 mm. long, and about 1 mm. wide, 

 placed transversely, and extending outwards nearly to the third 

 row of setse on each side, its margins thickened ; on the anterior 

 annuli of xix, xx and xxi similar but shallower depressions, or 

 only the ends of these may be shewn, the intervening portions 

 being more or less filled up, or marked only with a groove. The 

 genital ducts are in segment xviii, and judging from the situation 

 of their proximal portions the first of these f ossce ought to carry the 

 male pores near its extremities, but they are not visible externally 

 in any of the specimens. The others appear to be of the nature 



