450 W. BLAXLAND BENHAM. 
The clitellum occupies twenty-six segments; namely, 
xxi to xLv1 inclusive (i. e. rings 31—56) (fig. 1). There 
is not the slightest doubt that these rings are here true 
segments and not annuli; for the cheetee and nephridiopores 
are perfectly visible—indeed, better marked than on ordinary 
segments,—and the intersegmental grooves are deep. This 
clitellum is complete; its anterior and posterior boundaries 
are very well marked, and there are no lateral ventral ridges or 
markings analogous to tubercula pubertatis. The glandular 
thickening is continued right across the ventral surface, as in 
Diacheta and Pontoscolex. 
The extraordinary length of the clitellum is approached 
only by Allolobophora gigas (Dugés), where it occupies 
segments xxx to LI inclusive, 1. e. covers twenty-two segments. 
Amongst the Geoscolicide (Rosa) the clitellum is usually 
pretty extensive, covering some eight to ten segments, and in 
Diacheta thirteen segments. The great length of this organ 
in the present worm is the more noteworthy since in the only 
other member of the genus in which it has been observed, viz. 
in K. michaelsenii, it only covers seven segments, x1x to XXv 
(rings 27—33). Rosa states that it is quite evident, but finds 
that the inter-segmental grooves are reduced to simple lines, 
and are not as deep as in the non-clitellar segments. Again, 
in this species the longitudinal margins are evanescent, and do 
not pass beyond the ventral chetz, i.e. it is ‘‘incomplete.” 
The clitellum in Rosa’s species appears, then, to differ from 
that in mine—a difference that is not difficult to explain, as it 
is possible that the worm was not quite mature. 
We must wait till we can obtain a more abundant supply of 
these worms before we can settle this point; for although four 
species have hitherto been described, each species is repre- 
sented by only a single specimen, and of my three specimens 
only one has the clitellum fully developed. In a second I can 
detect traces of it in the smoother surface of a number of 
segments corresponding to the area occupied by the organ in 
the specimen just described, whilst in the third I can detect no 
trace of it. It is possible that, as in Moniligaster, which 
