STUDIES ON EARTHWORMS. 281 
examined by means of a lens it looks somewhat like the ciliated 
rosette of the sperm duct, but is much less folded. It is ciliated 
along its edges and on the surface; the appearance of the surface 
is of anumber of more or less hexagonal cells placed close 
together ; these are the ends of short columnar cells ciliated 
along their free surface (xp., Pl. XVI, fig. 14). The rosette is 
fixed to the septum at about its centre, and appeared to be the’ 
internal funnel of some duct, but this duct I was unable to 
find by dissection, owing to the muscularity of the septum. This 
rosette resembles the figure of the “ fimbriated organ ”’ described 
by Beddard in Pleurocheta (Megascolex) (86), the function of 
which he did not ascertain. In Microcheta it may be the 
funnel-shaped internal opening of a very delicate duct to 
convey to the exterior the products of a gland (y), which I 
will now describe. 
(6) On the anterior septum of somite x11 is a glandular- 
looking structure (y), whose function I do not know. It con- 
ststs of a dense mass of rounded cells arranged in a band, which 
is bent upon itself several times (Pl. XVI, fig. 8), the folds being 
close to one another. As, unfortunately, I did not observe it 
till after the animal had been in spirit, Iam unable to say what 
its appearance is when fresh; one might imagine it to be an 
ovary, whose duct is the organ just described, but its cells are 
not large enough, nor have they the characteristic structure of 
egg-cells. Has it something to do in the formation of the egg 
capsule, or is it connected in any way with copulation? I 
cannot say. But Megascolex (Pleurochzta of Beddard) (30) 
and Acanthodrilus, E. P. (14), have, similarly, organs in this 
region whose function is doubtful. 
Tue Vascutar System.—The blood system consists of the 
following longitudinal vessels, (2) Dorsal trunk, (0) a Ven- 
tral trunk, (c) a Typhlosolar trunk, (d) Lateral trunks, 
‘as well as lateral loops, amongst which are some strong com- 
missural vessels or “ lateral hearts” (Pl. XV, figs. 5, 6). 
There is no subneural trunk. 
(a) The Dorsal Trunk.—Lying on the top of the intestine 
is a thin-walled tube, constant in diameter, which is about one 
