1903.] -■ OLIGOCHiETA FKOM NEW ZEALAND* 217 



Sperm-sacs occupy segments xii., xiii., and eggs lie free in 

 segments xiv., xv. 



The chitinous peiiis is about ten times as long as the breadth of 

 its base (PL XXV. fig. 18); it is distinctly bent at a point just 

 below its outer end, and terminates in an asymmetrical, some- 

 what trumpet-mouthed expansion, which is apparently imperfect 

 on one side, as the chitin here becomes very thin (PI. XXV. 

 figs. 19, 20); there appears to be a "valve-like" arrangement, 

 somewhat like that figured by Yejdovsky for L, claparedianus (pi. xi. 

 figs. 7, 8). The muscles surrounding the penis are spirally wound. 



The spermatheca (PL XXV. fig. 21) has an irregularly pyriform 

 ampulla, connected to the pore by a narrow neck passing into a 

 short muscular duct, which is rather wider in the middle of its 

 course than at either end. The duct is much shorter than in the 

 previous species. The spermatophores (PL XXV. fig. 22), which 

 I observed in one instance, are dumbbell-shaped — i. e., an oval 

 constriction round its shorter diameter. 



Dimensions. Length 15-35 mm. ; diameter ^ mm. or ^ mm. 

 With 60 to 80 segments. 



Localities. Lakes Rotoiti and Taupo, North Island, New Zealand. 

 Obtained in considerable numbers at both places. 



RemarJcs. —Ihis, worm is much more slender than L. vejdovsTcy- 

 anus, and, like it, difiers from the majority of species of Limnodrilus 

 in possessing no integumental vessels, so far as can be made out in 

 preserved specimens. As the blood was distinct enough in the 

 intestinal network, it seems unlikely that I overlooked the vessels 

 on the body-wall, or going thereto. It appears to approach 

 L. dugesi Rybka *, from Mexico, from the diagnosis given by 

 Michaelsen ; but I have not access to the original paper in which 

 it is described. 



Limnodrilus sp. inc. 



From Lakes Wakatipa, Manapouri, and Waikaremoana some 

 immature specimens were obtained to which I will not give a 

 specific name, but which difier from either of the preceding species. 



The chsetse are in bundles of 4 or 5 anteriorly, but soon decrease 

 to a couple : or in some instances (the single individual from the 

 southern lake) the maximum, anteriorly, is two per bundle, and 

 posteriorly, both dorsally and ventrally, a single cheta. But in 

 both cases the form of the crochet is the same ; the upper prong 

 is much larger than the lower, indeed as much as twice the length, 

 and is much more slender and more elegantly curved, as it seems, 

 than in the preceding species ; the lower tooth is slightly stouter 

 than the upper. 



A more important difierence from the preceding species is the 

 possession of two pairs of swollen hearts in segments viii. and ix. 



In one case, although only the rudiments of the generative 

 organs are present, the epidermis is slightly, but definitely, thick- 

 ened on segments | x., xi., g xii. 



* Rybka, Mem. Soc. Zool. France, xi. p. 380. 



