36 MR. F. E. BEDDARD ON EARTHWORMS [Jan. 5, 



paper \ surmised that Fletcher's " Eudrilus dubius would prove to be 

 a Microscolex. This suggestion was later ^ shown to be correct by 

 the description of a species of Microscolex evidently identical with 

 Eudrilus dubius from the Argentine. I received myself, some time 

 since, a number of examples of a Microscolex from Madeira, through 

 the kindness of Mr. E. B. Poulton, F.R.S., which are described 

 above. The existing knowledge of the distribution of the genus is 

 as follows : — 



1. Microscolex modestus. Italy, Argentina. 



2. Microscolex dubius. Australia, Argentina. 



3. Microscolex algeriensis. Algiers. 



4. Microscolex poultoni. Madeira. 



The characters of M. algeriensis evidently necessitate a revision 

 of Rosa's generic definition given on p. 511 (3 of sep. copy) of his 

 memoir on the Argentine Earthworms. 



The following points are, I think, sufficient to distinguish this 

 genus from any other genera among the Cryptodrilidse. 



Genus Microscolex, Rosa. 



Microscolex, Rosa, Boll. Mus. Zool. Torino, vol. ii. no. 19. 



SetcB 8 per segment., distant. Clitellum on segments xiii., xiv., 

 XV., xvi., xvii., complete. S pores on xvii. No dorsal pores. 

 Subnervian vessel absent. Nephridia paired, present in genital 

 segments. Hearts, 3 pairs in segments x., xi., xii. Gitzard absent 

 or rudimentarij. Intestine without Igphlosole. Atria tubular, with 

 or without penial setce. Spermatotheca {if present) one pair in ix., 

 with diverticulum. 



The affinities of the genus have been discussed by Rosa, who com- 

 pares Microscolex with Photodritus and Pontodrilus. I may point 

 out that the absence of penial setae in Microscolex algeriensis 

 lessens the distance between tlie getms and Pontodrilus. 



The species which I describe here is quite clearly distinct from 

 the two others. The table (on p. 37) indicates the principal re- 

 semblances and differences between the four species Microscolex 

 dubius, M. modestus, M. algeriensis, and M. poultoni. 



* " Sui generi Pontodrilus, Microscolex, e Photodrilus," I. c. vol. iii. no. 39. 



- " Notes on Australian Earthworms," pt. iii., Proc. Liun. Soc. N.S.W. vol. 

 ii. ser. 2. 



^ " I terricoli Argentini raccolti dal Dott. Carlo Spegazziui," Ann. Mus. Civ. 

 Genova, vol. is. ser. 2. 



