8 
D. C. Danielssen. 
[No. i. 
with epithelium, formed of large, round cells with a round eccentric 
nucleus in which there is a round corpuscle (Pl. I fig. 9 b). Many 
of those cells are occupied by round shining bodies (undeveloped 
spermatozoa) (Pl. I fig. 9 c). Others are almost perfectly empty, 
but outside these there are seen great crowds of shining bodies 
similar to those found in the cells (Pl. I fig. 9 d). Among these 
crowds, many of the round shining bodies are seen to be furnished 
with a short tail (more perfectly developed spermatozoa) (Pl. I fig. 
9 e). It appears, here, as if the spermatogenesis proceeds from 
the spermatoblast's protoplasmic contents; perfectly different there- 
fore from what I stated to be the case with Edwardsioides vitrea, 
where the spermatozoa is supposed to originate principally in the 
cellular nucleus. 
On dissecting the animal, longitudinally, it appears that, unlike 
the Coelenterata, there is no so-called gastrovascular cavity to be found 
(Pl. I fig. 2). The gullet-tube is cylindrical, and about 10 m. m. 
in breadth at its origin (Pl. I fig. 2 e), but diminishes a little in thick- 
ness for a distance of 8-10 m. m., and then passes over into a 
thick intestine (Pl. I fig. 2 f), which becomes gradually narrower as 
it, in almost a straight line, extends itself down towards the post- 
erior extremity, where it passes over into the rectum (Pl. 1 fig. 
2 g) which opens into the previously described round anus (Pl. I. 
fig. 2h). 
Upon the outer surface of the gullet-tube and intestinal canal, 
12 septa are adherent, which, as previously mentioned, have their 
origin in the inner wall of the body, and extend themselves quite 
from the posterior extremity to the under surface of the oral disc, 
to which, also, they are attached. These septa divide the body- 
cavity (the Coelome) into 12 longitudinal chambers which, at the 
top, just under the oral disc, communicate with each other, inas- 
much as there is, in each septum, an oval aperture just at the 
point where the septum is secured to the oral disc (oral-stomata). 
There is no such communication posteriorly ; here the chambers 
close round the rectum, but at their bottom — formed by the 
body integument which is, here, somewhat less thick; between the 
previously mentioned papillæ, or really the terminal posterior in- 
sertions of the septa — there is found a fine fissure which is 
opened and closed by a fold that appears to form a kind of valve 
(Pl. I fig. 13 a). This fissure places each chamber in communica- 
tion with the external medium (the sea-water), and must be consid- 
ered as really a genital pore. Whether the seawater flows into the 
