MONILIGASTER GRANDIS, A. G B. 309 
worm full of earth), but if a starved worm, from which most of 
the earth has been. voided, is killed by immersion for a few 
minutes in strong spirit and then stretched, it may be very 
clearly seen that the body tapers from Segment vuit, gradually 
but regularly, right away down to the tail end, which is then a 
blunt point. If such a worm is left in strong spirit until all the 
muscles have been contracted and become firm and hard, the 
region immediately in front of the anus becomes swollen out _ 
into a knob. I think that this is due to the strong contraction 
of the thick layer of longitudinal rectal muscles. 
This particular shape and this great variation in the size of 
the segments is not by any means common among earthworms, 
and does not obtain, for instance, in the majority of Monili- 
gasters. 
As a rule the segment is clearly divided into two anuuli, 
while each of these is again obscurely divided (at any rate in 
about the anterior half of the worm) into two, making in all 
four annuli (see fig. 15, Segment xv). The sete are placed 
upon the second of these four annuli. The fourteen anterior 
segments are peculiar in their annulation. Segments 1, 11, and 
111 consist of one annulus only, and Segments tv and v of 
two annuli only, while in Segments vi—x there are more than 
the usual number of annuli, but the additional annuli are very 
irregularly marked and frequently do not extend round the 
whole circumference. Fig. 3 is accurately drawn from one in- 
dividual. When the clitellum is developed the annulation 
in that region disappears, but I have never seen the demarca- 
tion between the segments disappear or even become to any 
great extent obscured. 
Prostomium.—This is not dovetailed into the peristomial 
segment (Segment 1), but is very definitely marked off from it 
by a groove. The anterior edge of the peristomial segment is 
almost always turned in, so that the prostomium appears to 
protrude from the buccal cavity. When the prostomium is 
fully protruded a portion of the buccal membrane is protruded 
also (see fig. 4). It can be entirely withdrawn, and in spirit 
specimens is usually invisible (in fig. 15 the prostomium is 
