THE GIANT EARTH-WORM OF GIPPSLAND. 49 
20th, and anterior part of the 21st segment. The sete are seen as far forward as the 
12th segment, in front of which they cannot be detected. The outlines of the 
segments are clear, and much more strongly marked than the annuli. The figure 
shows the tapering anterior end, the swollen part succeeding this, then a somewhat 
narrower portion, and then the swolien clitellar region. 
Fig. 2.—Represents a mature worm, dissected from the dorsal surface. The 
body wall is cut open by a median incision, and the organs represented in situ. 
Anteriorly are the very strong cup-shaped septa (sept.), bound together by special 
muscular slips (m.), and completely concealing the alimentary canal from view. 
Passing backwards, they gradually become much thinner, and more membranous in 
appearance, until, in the 19th segment, they entirely lose their muscular nature. In 
especially segments 15-18 inclusive, the muscular slips are very long, and pass from 
one segment to another. The septum of segment 15 forms a special covering for. 
the dilatation of the alimentary canal (dil.) The blood-vascular system is coloured 
red. Anteriorly, only the strong muscular lateral vessels (t7. v.), or “hearts,” can be 
seen. Behind the 15th segment, the dorsal blood-vessel is seen, with a pair of 
transverse vessels passing off from each side in every segment to the walls of the 
alimentary canal (tr. v.) In segments 12, 13, and 14 the racemose vesiculz seminales 
(vs.) project from between the strong septa, and in segment 18 the two prostate 
glands push aside the septa, which are here membranous and transparent enough 
to allow of the coiled glands being, in part, seen through them. The walls of the 
body cavity are lined by an enormous number of small coiled tubules—the nephridia 
which are especially abundant in the clitellar region. 
Behind the part which is cut open, four segments are shown, with the large (very 
evident dorsal) pores (dp.) lying in the lines of division. 
Fig. 3.—A diagrammatic longitudinal vertical section through the anterior part 
of the worm. The alimentary canal runs through the centre, divided into a thickly 
walled pharynx (phar.), as far back as the end of the 4th segment ; a short cesophagus 
and thick walled gizzard in the 5th segment; a tubular portion of the intestine in 
segments 6-11 inclusive ; a dilatation of the intestine in each of the segments 12-18 ; 
the tubular intestine behind these. The reproductive organs are represented. The 
two receptacula seminis in the 8th and 9th segments, with their ducts running 
forwards so as to open just with the next segment in front of that which contains the 
organ. Hach receptaculum (vr. s. 0.) has a slight diverticulum near the fixed end. 
The testes, (t¢., the second one is marked by mistake vd.) attached by short stalks to 
the anterior septa of segments 10 and 11. The two internal openings of the vasa 
deferentia (vd. 0., and vd.2 0.) The two vasa deferentia, running quite distinct from 
each other (vd., and vd.) to open in the 18th segment into the prostate gland (pr-), 
which opens to the surface in the same segment (mo.) The ovary in segment 13 (o.) 
The internal opening of the oviduct in segment 13 (od.) The external opening in 
segment 14 (fo.) The vesicule seminales (vs.) in segments 11-14 inclusive. The 
H 
