STRUCTURE OF THREE NEW SPECIES OF EARTHWORMS. 107 
The longitudinal muscles have their fibres arranged in that 
remarkable bipinnate fashion which is found in many species 
of Lumbricus and Allolobophor a, but is comparatively rare 
elsewhere. 
With regard to the vascular system, the only facts which 
I am able to record are, (1) the condition of the dorsal vessel ; 
(2) the number and connections of the “hearts.” 
The dorsal vessel is a completely double tube, with the 
exception of that portion which lies in the first four or five 
segments. It resembles the dorsal vessel of Acanth odrilus 
multiporus in the fact that the two tubes are perfectly separate 
throughout, except where they become permanently fused at 
the anterior extremity of the body. The somewhat contracted 
condition of the worm frequently caused the two halves of the 
dorsal vessel to become widely separate in the middle of each 
segment, while at the mesenteries they come into close rela- 
tion ; there is, however, no fusion of the two tubes at these 
points, such as occurs in A. novae zealandise and Micro- 
chaeta. I observed six pairs of lateral “hearts,” the last 
pair being in segment 13 : the last four pairs are specially 
large, and are connected with the supra-intestinal as well as 
with the dorsal vessels. The anterior two pairs (there are pro- 
bably one or two pairs in addition to those which I have 
mentioned) are much more slender and only connected above 
with the dorsal vessels. 
Septa. — The septa separating segments 8 — 9, 9 — 10, 
10 — 11, 11 — 12, 12 — 13, are thicker than the rest, but not to 
so marked a degree as is often met with in Earthworms. 
Alimentary Tube. — The pharynx has the usual charac- 
ters. The gizzard lies in segments 6 and 7 ; the oesophagus 
is thick walled and highly vascular, but there appeared to 
be no distinct calciferous glands. 
The intestine has a typhlosole (PI. XIII, fig. 8). 
The nephridia are not obvious on dissection except in 
segments 2, 3, and 4 ; in each of these segments is a tuft of 
nephridial tubules of considerable size; in the posterior seg- 
ments nephridia are present, and open on to the exterior by 
