NEW GENERA AND SPECIES OF EARTHWORMS. 269 



The alimentary canal is entirely without a gizzard ; after the 

 pharynx the narrow oesophagus extends for a considerable dis- 

 tance, terminating in the intestine in Segment 17. The first 

 part of the cesophagus as far back as Segment 9 is not greatly 

 vascular ; the rest of the oesophagus is particularly richly 

 supplied with blood-capillaries ; it has, however, no calciferous 

 glands or diverticula of any kind ; the terminal section of the 

 oesophagus, occupying Segments 13 — 15, is wider than the por- 

 tion in front; the intestine is at first (for one segment) hardly 

 wider; it suddenly increases to double the previous width. 

 There seems to be no typhlosole. I have not attempted to 

 work out the anatomy of the circulatory system, but the few 

 following points may be noted. In Segments 8 — 13 are a series 

 of hearts connecting the dorsal with the ventral blood-vessel ; 

 there seems to be no supra- oesophageal vessel. 



§ Affinities of Siphonogaster. 



In the incomplete description of the worm, which was based 

 upon examples kindly forwarded to me from Kew by Mr. 

 Thiselton Dyer,^ I pointed out certain apparent difi'erences 

 from Siphonogaster segyptiacus of Levinsen. The exa- 

 mination of the large series of well-preserved specimens re- 

 cently received from Lagos through the kind instrumentality 

 of Mr. Alvan Millson leads me to the belief that there is only 

 one species of Siphonogaster; the only possible difference 

 that I can see is that in Siphonogaster segyptiacus the 

 setae upon the peuial appendage are irregularly disposed ; in 

 all the worms from Lagos these setse are largely paired, though 

 not perfectly regular ; in any case there were very rarely more 

 than two setae in a transverse row. Levinsen's account is 

 necessarily so imperfect that the question of the species cannot 

 yet be decided. Hence I retain provisionally the specific name 

 applied by me to these worms. 



Dr. Michaelsen has lately described two other species of 



' "On an Earthworm of the Genus Siphonogaster from West Africa," 

 ' Proc. Zool. Soc," 1891, p. 48. 



