184 TRANSACTIONS. 
removed, the skin being pinned to the table, the heart, with 
pericardium, lung, and pleura remaining zz stfu. The blood 
enters the auricle by the pulmonary vein, passes from the auricle 
to the ventricle, is pumped into the aorta (which arises from the base 
of the ventricle), and divides into an anterior and posterior aorta. 
The anterior branch passes the generative organs under the intes- 
tine and on to the brain or large nerve centre, as the carotid 
artery, on its way giving off a branch to the generative organs, and 
other branches to the foot crop, buccal mass, head, &c. The 
posterior branch supplies the liver, stomach, intestine, and the 
posterior part of the generative organs. The blood is returned to 
the lung by venous sinuses, when after passing through the lung 
is returned to the heart by the pulmonary vein. 
Liver.—The liver, or digestive gland, is large in proportion to 
the other viscera. It is a brownish yellow colour, and divided 
into two principal lobes. I believe the secretion from each lobe is 
conveyed to the intestine by separate ducts. It fills the cavities 
between the lobes of the ovo-sac and the stomach. The herma- 
phrodite gland, or ovo-testis, is embedded in its substance. 
Digestive System.—The mouth, when closed, has a puckered 
or drawn-in appearance. It is furnished with a ribbed, horny, 
crescent-shaped superior maxilla, with a posterior projecting plate, 
which forms the hard palate, and to which the muscles are attached 
which move it. The mouth opens into the buccal mass or pharynx, 
which is a rounded muscular lump. From the lower and posterior 
surface of its'cavity a pale diverticulum depends. This is the sac 
of the lingual ribbon or tongue. Although sometimes called by the 
latter name, it has no likeness to that on which our ordinary ideas 
of such an organ are founded, for instead of being a projecting 
body lying in the cavity of the mouth, it is to some extent a sac, 
which passes backwards and downwards, the open end opening 
vbliquely upon the floor of the mouth. When this sac is dissected, 
laid open, and examined, it is found to be covered with small teeth, 
which have a superior and inferior process on those near the centre 
line of the ribbon. The inferior process gradually lessens from the 
centre to the side, and in the side teeth it is wanting. There are 
112 rows, each row having 26 teeth on each side of the middle 
line, and is expressed : 26 + 26 x 112 = 5824 teeth, each measuring 
1-500th of an inch in length. Below, and overlapped by the open 
end of the ribbon, is a tooth-like cartilage, hinged, and resembling 
to some extent the epiglottis. I have had some difficulty in 
