aT COBBOLD, ON A NAKED-EYED MEDUSA. 
lateral and twisting contractile movements of the peduncle, 
but viewed from above, while empty and im a state of rest, 
the walls were symmetrically disposed in the form of a cross 
(fig. 7). With the help of a pocket-lens the lips presented a 
finely granular or ground-glass-like appearance, which was 
due to the abundance of those minute fusiform cellules form- 
ing, as we have seen, the general parenchyma of the body. 
The functionally combined respiratory and nutritive sys- 
tem of vessels, or gastro-vascular canals, are five in number— 
four radiating and one cireumferential—as in other gymnoph- 
thalmatous genera; their walls are transparent, well defined, 
and rigid. The smaller kind of the contained corpuscles are 
rather less in diameter than human blood-globules; while the 
larger, apparently mother-cells, are nearly three times greater, 
possessing nuclei of variable size, but frequently identical in 
character with the lesser globules. All are transparent and 
colourless, with the limiting membrane sharply marked (figs. 
9, 10, 11). When the circulation was active, the corpuscles 
moved in a moderately rapid and regular manner, their course 
in the radiating vessels being continuous from one half of the 
hemisphere to the other. In other words—two vessels carried 
the particles from the marginal canal, convergingly, to the 
central point of intercommunication, on the one hand, and 
two conveyed the same elements from the centre, divergingly, 
on the other (fig. 7). The behaviour of the corpuscles led me 
to conjecture the presence of cilia within the canals, though 
they were not structurally demonstrated. In regard to the 
presumed continuity of the vessels with the stomach in this 
genus, at the summit of the umbrella, let it suffice me to add, 
that I could discover no opening or any interposed channel 
of communication. The enlarged central vascular space 
formed at the crossing of the radiating canals, was the only 
indication of a supra-stomachal cavity ; through this space the 
corpuscles rolled on uninterruptedly (fig. 11). 
The reproductive glands—four in uumber, elongated or 
semiclavate—are placed on the inferior surface of the sub- 
umbrella, a short way distant from the margin, and in the 
course of the radiating canals. Their border to the naked eye 
was smooth, but under a half-inch objective the surface looked 
undulating, an appearance due to the bulging of the ovarian 
cells lying immediately beneath. Each gland was subdivided 
by one of the radiating vessels traversing its long axis (fig. 6). 
The subjacent ova at the surface severally displayed an outer 
cell-wall with its included transparent albumen, a second 
membrane surrounding the molecular yolk, and a third con- 
stituting the germinal spot, within which were three or four 
