STEUCTUEE OP THEEE NEW SPECIES OF EAETHWOEMS. 113 
furrow upon segment 9 ; the second is situated a little an- 
terior to the boundary line between this and segment 10 ; 
the third is placed a little behind the first furrow of segment 
10. It seems to me probable that these septa are those which 
should separate segments 8, 9, 10 ; but so little do they corre- 
spond to the external divisions of the segments in question, 
that the space enclosed by the two last septa, which should 
correspond to segment 10, actually has no setae. The setae of 
this segment occur behind the septum, and therefore, so 
far as the septa are concerued, in segment 11. The presence 
of a pair of transverse vascular trunks between each of these 
mesenteries is, however, a conclusive proof that they enclose two 
segments (see description of vesicula seminale, p. 114)". 
§ Vascular System. — As in the majority of Lumbricidae, 
there is a dorsal vessel, a supra-intestinal, a ventral vessel, and 
two lateral trunks. The dorsal and ventral vessels communicate 
in segments 8, 9, and 10, by a pair of transverse vessels, a 
pair to each segment. In the two following segments are two 
pairs of stouter transverse vessels, which also communicate 
with the supra-intestinal vessel (PI. XII, fig. 6). 
The lateral trunks are very conspicuous in the gizzard seg- 
ments. At each end of the gizzard they give off a system of 
branches, which supply it with blood ; behind the gizzard the 
two lateral trunks run beneath the intestine, and each ap- 
proaches very closely its fellow. I am unable to state how 
the lateral trunks originate. 
§ Nephridia. — The nephridia of this species consist of in- 
numerable delicate tubules, which are chiefly developed in the 
anterior segments of the body ; they are at any rate more con- 
spicuous here than elsewhere. As in T. orientalis, there is a 
special mass of these tubules in the first and second segments 
of the body. The characters of the nephridia in this genus 
resemble those of Perichaeta, Acanthodrilusmultiporus, 
Trigaster, &c., so far as the naked-eye appearances are con- 
cerued. I have ascertained by cutting sections of a portion of 
the integument in the region of, and including the orifice of a 
spermatheca, that in this part of the body, at any rate, there is 
