50 



MR. F. B. BEDDARD ON AN 



[Jan. 20, 



On the eighteenth segment, as ah'eady mentioned, the ventral 

 <;ouples are absent, but the dorsal couples are present. 



The shape of the setee is very characteristic and is correctly given 

 by Levinsen {loc. cit. pi. vii. fig. 6). I could observe no differences, 

 except with regard to size, on any part of the body. Their colour 

 is, hovpever, somewhat remarkable. The setse of Earthworms are 

 generally of a "horn-yellow" colour. In this species the colour 

 appears to be much the same ; but when a seta is viewed with the 

 light passing from below through its entire length it appears dis- 

 tinctly red. 



The appendages of the eighteenth segment are of an oval form 

 (fig. 2, a, h), with a narrow neck connecting them with the body- 



Ym. 2. 



a . h 



Appendages of Si;p7ionogaster millsoni. 



a, ventral view ; b, lateral view of segments xvii-xx, showing the processes of 

 the body-wall A ; S, setse. 



wall ; there was no trace of any infolding of the margins such as 

 Levinsen fi.gures. 



Each appendage is furnished, as in S. cegyjjtiacus, with a number 

 of peculiar setse, the shape and arrangement of which is rather 

 different from that which characterizes *S'. cegyptiacus. 



In that species there are three or four irregular series of the setse, 

 beginning at about the end of the first third of the appendage and 

 reaching to its very extremity. In &. millsoni the seta; are disposed 

 in two parallel lines, each of which is near the lateral margin of the 

 appendage ; they lie upon the posterior surface of the appendage. 



The setse themselves are shaped, as in S. cegyptiacus, like a spear- 

 head with a very short shaft ; but in (S. millsoni, as shown in the 

 accompanying drawing (fig. 3, p. 51), which may be compared 



