166 Christmas Island. 



YEEMES.^ 



OJS" THE EARTHWORMS EROM CHRISTMAS ISLAND. 



By Da2^iel Rosa, D. Sc, 



Assistant in the Royal Zoological Museum, Turin. 



1. Pontodrilus ephippiger, D. Rosa (1898). (Eigs. 1, 2.) 

 D. Eosa: Ann. Mag. Nat. Hist. [7], vol. ii (1898), p. 281, pi. ix, figs. 4, 5.. 



1 2 



Fontodrilns epliippiger, D. Eosa (1898). 



Fig. 1. Prostate. 

 ,, 2. Spermatheca. 



Hab. — Christmas Island (near small stream on east coast). 



The length of our specimens ranges from 43 to 47 mm., witli 

 a diameter of 3 mm. ; the number of segments varies from 85 to 

 100 ; the colour (in spirit) is an intense yellow. 



The prostomium is short, only slightly dovetailed in the peri- 

 stomium, which is longer than the second segment. 



The setae are distant : behind the clitellum the ventral interval 

 aa is twice that between setae ab ; the lateral intervals between 

 setae ab, be, cd are about equal, though slightly increasing from 

 below upwards ; the dorsal middle space dd is about three times as 

 wide as cd. These distances vary slightly in front of the clitellum ; 

 for instance, at the height of the spermathecae the setae be are 

 slightly wider apart than setae ab or cd, so that the setae are here 

 paired, though, of course, not very close together. 



The clitellum extends over segments 13-17= 5; it may be 

 termed saddle-shaped, ceasing near the outer ventral seta {b) : this 

 clitellum is well developed dorsally, where its rings are completely 

 fused together, while on the ventral area the setae as well as the 

 intersegmental furrows are tolerably visible. 



There is a deep transverse fossa on segment 1 8 ; the transverse 



^ Eeprinted, by permission, from Ann. Mag. Nat. Hist. [7], vol. ii (1898),, 

 p. 281, pi. ix, figs. 4-7. 



