184 Transactions. 



removed, the skin being pinned to the table, the heart, with 

 pericardium, hmg, and pleura remaining in situ. 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 

 obliquely upon the floor of the mouth. When this sac is dissected, 

 laid open, and examined, it is found to be covered wdth 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 -i- 26 x 112 = 5824 teeth, each measuring 

 1 -500th of an inch in length. Below, and overlajjped 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 



