neio G 671118 of OUgochcvta. 01 



differed in the form of the diverticulum. My description of 

 Neodrilus has recently * been confirmed and extended by- 

 Mr. Benliam, and I myself have since received additional 

 examples. It is clearly a distinct species, but not, as I now 

 think, a distinct genus. Both this instance and that afforded 

 by Gordiodrilus ditheca seem to show tliat the doubling of 

 the atria is not quite so important a character as I and others 

 have been hitlierto inclined to regard it. The possession of 

 one or of two pairs of atria need not, as I now think, hinder 

 species from being placed in the same family, or even genus, 

 if their other characters support such a juxtaposition. 



5. Gordiodi'ilus dominicensis^ sp. n. 



(PI. VI. tigs. 2, a.) 



Of this species I have received about half a dozen examples 

 from Kew ; the habitat of the worm is the island of Dominica, 

 in tlie West Indies. 



Tlie worms were all of the same size ; one selected for 

 measurement was 26 millim. in length by a breadth (at tlie 

 head end) of 1 millim. It consisted of about eighty segments. 

 The species is of the same build as Gordiodrilus elegans ; 

 and so alike are they in external characters that at first I 

 thought that I was dealing with the latter species. It will 

 be seen, however, from the following description that they 

 are by no means identical. 



External Characters. 



The setai are strictly paired and of the usual Lumbricid 

 pattern. They are not modified in size or shape anywhere. 

 Only the ventral pairs are absent upon the xviiith aufl xixth 

 segments where the atrial pores open. The anterior seg- 

 ments are narrower — have a less antero-posterior diameter — 

 than those which follow ; from and including tlie seventh 

 segment each is divided by a furrow into two parts. This 

 furrow as nearly as possible coincides in position with the 

 setas. Further back still tlie segments are marked by more 

 numerous furrows. 



The prostomium is continued by furrows to nearly the 

 posterior boundary of the buccal segment. 



The nephridiopores are in front of the lateral pair of setai; 

 they can usually be fixed to one or other of tlie two setse of 

 the pair, and in fact show an alternation in position; somc- 



* " Notes on Two Acanthodriloid Earthworms from New Zealand, 

 Q. J. M. S. vol. xxxiii. p. 289. 



