56 A. 0. OUDEMANS, 
cesophagus, the nephridial canals float. They are not attached 
against the longitudinal muscular layer (or this is a peculiarity 
of the specimen I examined?). The nephridial canals here 
are thicker and more distinct than I have ever seen, but have 
the same character as all the nephridial canals hitherto examined 
(of course with the exception of Carinella). In one of the 
canals I very distinctly saw cilia a little longer than the 
cells. 
I have found only one pair of excretory ducts. They were 
very easily to be observed, not only lying above the nerve 
stems, but were even directed straight upwards, and their 
pores lay in the longitudinal dorsal groove or fold formed by 
the upwards-turned edges of the body (cf. Hubrecht, 35). 
About the region of the two pores the medial vessel left 
the proboscidian sheath, having shown again, as in all 
Schizonemertea, the different character in its upper and 
lower wall. Behind the pores the nephridial system extends 
still a little further backwards. 
In the meantime the lacune surrounding the cesophagus 
have gradually become larger, and afterwards again smaller, 
till they pass into the two vessels situated beneath the intes- 
tine. Thus in the intestinal region we find three longitudinal 
vessels ; they are usually united by transverse vessels, and 
though the diverticula are narrow I saw very distinctly a 
transverse vessel over each diverticulum. But these trans- 
verse vessels do not lie so closely against the diverticula as in 
Valencinia. In Langia they lie free amidst a gelatinous 
stroma with large nuclei (figs. 62—64), as do also the three 
longitudinal vessels. These nuclei are generally arranged 
round the vessel. Several of the nuclei had about them an 
irregular protoplasmic substance, generally showing offshoots 
arranged radially round the vessel. The stroma, too, pre- 
sented radial arrangement, which is probably to be ascribed to 
local thickenings caused by the contraction of the vessel in the 
gelatinous tissue. Fig. 62 shows us one of the lateral (ventral) 
vessels cut transversely ; fig. 63 the same, with an outlet of a 
transverse vessel, the latter, of course, cut longitudinally ; 
