4.48 W. BLAXLAND BENHAM. 
This secondary ringing becomes more marked as we pass back- 
wards, and the thirteenth ring is marked by two slight grooves, 
dividing it into three well-marked secondary rings. This same 
phenomenon is presented by the following rings up to about the 
twenty-second, after which it becomes less and less distinct, till 
it is scarcely recognisable on the thirtieth ring. These rings, up 
to about the twenty-fifth, are all of nearly the same size. The 
rings of the clitellum are not thus marked, but the post-clitellar 
rings are biannulate dorsally. Any zoologist, even one familiar 
with earthworms, examining these rings would regard them, 
I do not doubt, as “segments ;” but such is not the case in 
the anterior part of the body. The twenty-third ring and every 
subsequent ring is a “segment” (a somite), as is shown by the 
internal anatomy—septa, nephridia, blood-vessels, as well as by 
the chetz,—but anteriorly to this most of the rings are 
“annuli,” or secondary ringings of the body, two of which go 
to form a “segment” (fig. 1). This, again, is shown by 
internal anatomical arrangements, and the only doubtful rings 
are the most anterior three or four. From the position of the 
nephridiopores, I believe that the first (sometimes annulated) 
ring is a segment; the second and third rings make up the 
second segment. The segment 111 is also biannulate, but the 
fourth segment is not annulated; each of the following seg- 
ments, v to x11 inclusive, are biannulate, behind which every 
segment consists of only one ring or annulus (see fig. 6). 
Rosa construes the anterior rings rather differently. He 
believes the first two rings constitute the first segment, and that 
each of the next two rings is a segment, and that the fourth 
segment is biannulate. Beyond this point we are in accord. 
The point of difference, then, is that we have six rings at 
the anterior end to fit into four segments. Now, as we shall 
see, the most anterior nephridium opens at the anterior margin 
of the second ring, the second nephridium between rings 3 and 
4, the third between rings 5 and 6. At this point also is the 
first septum. 
Proceeding now with the description of the external anatomy 
of K.cingulatus. As in three of the other species, there 
