1892.] SPECIES OF EARTHWORMS. 677 



but in segments xiv. and xv. the oesophagus becomes wider, and its 

 lining membrane much folded and very vascular. This region 

 evidently corresponds to the calciferous glands of other Earthworms : 

 all doubt upon the matter appears to be removed by the discovery 

 of crystals exactly similar to those vrhich occur in the calciferous 

 glands of other Ohgochseta. The vascularity of the oesophagus is 

 not limited to these tvFO segments ; from the tenth segment onwards 

 its walls are vascular, though not so folded as in the two segments 

 xiv. and xv. The intestine commences in the xviiith segment. 



The gonads occupy the usual position ; the sperm-sacs are in 

 segments is., x., xi., xii. The atria are like those of other Acantho- 

 drilidse, and each is provided with a bundle of penial setae. These 

 setae (Plate XLVI. figs. 9 and 10) are recurved at the extreme end; 

 the extremity has two delicate wing-like processes which, when the 

 seta is viewed from above, give to the end an oval contour ; the tip of 

 the seta in this aspect is seen to be bifid. The absence of any orna- 

 mentation upon the setse appears to distinguish the New Zealand 

 Acanthodrilidse with the exception of Octochcetus antarcticus, where 

 it is only very slight. 



The spermatothecse are, as is nearly universally the case with the 

 Acanthodrilidse (Acanihodrilus [^Diplocardia] communis is, so far as 

 I am aware, the only exception), two pairs situated in segments viii. 

 and ix. Each pouch has three small diverticula, one of which is 

 constantly in front of the septum. 



4. Acanthodi'ilus paludosus, n. sp. 



This is a small and slender worm, but I have not preserved any 

 accurate notes of its dimensions ; it was about an inch in length and 

 something like 1 mm. in diameter. It was found in a marsh in 

 New Zealand by Mr. W. W. Smith, to whom I am indebted for the 

 specimen. 



This species is a near ally of Acanthodrilus annecfens, which I 

 have already referred to as possibly worthy of generic separation 

 from the Acanthodrilidse with paired nephridia. 



The present species has the same arrangement of the setae, which 

 are not modified upon any of the segments of the body. I did not 

 describe, in my account of Acanthodrilus annectens ^, the fact that 

 only one of the two ventral setse is missing on the segments which 

 bear the atrial pores, i. e. xvii. and xix. ; theapertures take the place 

 of the missing outer seta of the ventral couple ; on the xviiith seg- 

 ment both setee of the ventral pair are present ; the pore itself lies 

 to the outside of the pair. Acanthodrilus paludosus shows exactly 

 the same arrangement, and both species therefore differ from Acan- 

 thodrilus smithi and from the other New Zealand species of Acan- 

 thodrilus in this matter : in them the ventral setse are entirely 

 absent from the xviith and xixth segments. 



The clitellum was not developed, though in other respects the 

 worm appeared to be fully mature. 



^ " On the Structure of three new Species of Earthworms &c.," Q. J. M. S. 

 vol. xxix. p. 102. 



