174 W. B. BENHAM. 



drilidse which, having become aquatic iu habit, has uuder- 

 gone certain modifications, which give it a resemblance at first 

 sight to Criodrilus, an aquatic Lumbricid ; for example, 

 the loss of a gizzard, the disappearance of nephridia from the 

 anterior somites, the vesicular character of the coelomic epi- 

 thelial cells surrounding the nephridia, the peculiar modifi- 

 cations in the vascular system — viz. the breaking down of a 

 network on the gut to form a sinus — and the longitudinal 

 tegumentary vessel, and the absence of dorsal pores. 



Systematic. 



Family Rhinodrilidse, raihi. 



Sparganophilus, nov. gen. 



Clitellum extensive, occupying nine or ten somites; 

 bounded latero-ventrally by tubercula pubertatis. 



Prostomium not marked off from the peristomium. 



Male pores inconspicuous, between Somites xviii and 

 XIX, without accessory organs. 



Sperm-sacs, two pairs; no median sac. 



Spermathecae simple; three pairs. 



No gizzard nor oesophageal diverticula; no typhlosole. 



Vascular System. — The only commissural vessels are 

 situated anteriorly; perienteric blood-sinus; no subneural vessel. 

 A couple of longitudinal tegumentary vessels on each side 

 traverse the anterior somites, and have no connection with 

 the gut wall. 



Species S. tame sis, n. sp. 



Since only a single species is known, it is well-nigh 

 impossible to separate specific from generic characters. 



Distribution. — There is but little doubt that the home of 

 the B/hinodrilidse is America, and the occurrence in England 

 of a member of the Rhinodrilidse is very striking. Hitherto 

 only one member of the family has been discovered in Europe, 

 viz. Hormogaster, from Italy ; the more typical genera, An- 

 teus, llhiuodrilus, and Urobcuus, being South American. 



