ON KYNOTUS CINGULATUS. 44,7 
fact, too, which is of interest, as adding to our knowledge of 
the varied modes of copulation amongst earthworms. 
External Anatomy.—The details refer to the specimen 
provided with a clitellum, and preserved in the British Museum, 
which I have not opened or otherwise injured. 
This worm contains three hundred and fifty-six rings,! most 
of which are true segments, though some of the anterior rings 
are only “annuli.”’ Its length is 225 mm., its diameter about 
12 mm. in front of, but scarcely half this behind the clitellum. 
The posterior end was truncated, and the worm had evidently 
been cut through, probably at about half its length. The 
pre-clitellar region measures about 57 mm. (one and a half 
inches); the clitellum itself is 50 mm. (two inches) long. 
After the first dozen rings the body narrows slightly, then 
at the twenty-third ring gradually widens again, whilst at the 
thirty-first ring the diameter increases suddenly ; this diameter 
is retained throughout the clitellum, behind which, at the 
fifty-seventh ring, the body suddenly diminishes in diameter. 
The body is cylindrical and strongly contracted, so as to 
feel quite hard in the anterior region. 
The general colour of the worms, in spirit, is dull buff; 
the dorsal surface behind the clitellum is black, and similar 
black pigment occurs on alternate rings in front of this organ. 
I have been unable to detect a prostomium ; there is no trace 
of it externally, and on slitting open the buccal cavity of one 
of the specimens I saw no trace of it in a retracted condition. 
This is the more curious, since K. longus is provided with a 
large prostomium, and Rosa mentions it in his species. 
The first two rings and part of the third are marked by 
longitudinal grooves, as in other species (Pl. 33, fig. 1). The 
first ring is obscurely divided into two by a furrow, which in 
one specimen was so distinct as to cause me on first counting 
to reckon this ring as two rings. 
The fourth and following rings are marked by a distinct 
ridge round nearly their middle, dividing each ring into two. 
1 Tuse the term “ring” to indicate the apparent segment: that is, what 
anyone would at first sight regard as a “‘ segment.” 
