ZOOPHYTA HELIANTHOID A. 
197 
The body of the Heliantho’ida may be compared to a trun- 
cated cone or short cylinder, seated on a flat plain base, while 
the opposite end is dimpled in the centre with the oral aperture, 
and garnished with variously figured tentacula which originate 
from a space between the proper lip and the free somewhat 
thickened border of the disk. In a state of contraction the 
mouth is closed, the tentacula are shortened, and the whole 
concealed by this border, being drawn like a curtain over them, 
leaving a mere depression on the top. The mouth leads by a 
very short and wide passage into a large stomach, which is a 
membranous bag puckered internally with numerous plaits, and 
divided in a perpendicular direction into two equal halves, by a 
deep smooth furrow with cartilaginous sides, as was first remark- 
ed by Reaumur.* There is no intestine, nor any other visible 
exit from the stomach than the mouth, by which the undigested 
remains of the food are ejected, always enveloped in a large 
quantity of a clear glairy fluid. But in a state of expansion and 
of hunger, many kinds of Heliantho'ida can protrude the stomach 
beyond the lip in the form of large bladder-like lobes, which 
often hang over the sides and almost conceal the rest of the 
body ; and amidst them there are very frequently extruded at 
the same time some white filaments, like bundles of ravelled 
thread, which have escaped either through a rupture, or a cir- 
cular opening in the bottom of the stomachal membrane. The 
space between the walls of this organ and the outer envelope is 
divided into numerous narrow compartments by perpendicular 
and parallel lamellae of a musculo-tendinous texture, which ex- 
tend from the oral disk to the base, and radiate to the centre 
like the gills of a mushroom to its stalk, — a comparison the more 
exact as some only of the lamellae reach and touch the stomach, 
the rest coming more or less short, and forming consequently 
imperfect interseptal spaces. “ The breadth of the leaflets va- 
* “ They (the furrows) are produced on each side by the firm adherence of 
the gastric membrane to a pair of very dense, fleshy, but narrow leaflets, through- 
out their whole extent, or, in other words, from the top to the bottom of their 
internal border. These depressions divide the animal into two lateral halves, 
constituting a bilateral symmetry in Actinia, as has been observed by M. Agassiz 
in other supposed radiated animals.” Teale in loc. cit. 102 But in Actinia 
Dianthus the channel or furrow exists on one side only. 
