GADUS. 333 
The heart lies in the former and the alimentary canal and other organs 
in the latter. The somatic layer of peritoneum is deeply 
Alimentary. pigmented, forming a black wall to the cavity, whilst the 
splanchnic forms a glistening transparent membrane sur- 
rounding the alimentary canal and forming a dorsal mesentery. 
The teeth have already been mentioned : they are borne on the pre- 
maxilla and dentary and a small inner patch on the vomer (cf Frog). 
If the jaws be pulled open and the pharynx examined, the five lateral 
gill-clefts can be noticed and in addition a large paired patch of teeth on 
its dorsal surface, borne on the superior pharyngeal bones or upper 
bones of the branchial arch. Inimediately ventral to these are a pair 
of patches of teeth on the inferior pharyngeal bones, representing the 
Fig. 236.—DIssECTION OF HADDOCK FROM THE LEFT SIDE. (4d ma?.) 
Closed Duct of Air-bladder. 
Kidney. 
Liver. Body-wall. 
Air-bladder. 
Kidney. 
Urinary 
| Bladder. 
Ureter. 
Gills, 
Heart, | |. Anus, Genital Aperture. 
e | Gonad. 
(Esophagus. Rectum. 
Gall- . “a vi 
bladder. Pyloric Stomach. Liver. Spleen. - 
Ceca. : 
The left abdominal wall has been cut and thrown back dorsally, and the intestine and 
stomach have been pulled out ventrally. 7 
fifth branchial arches. These teeth, working upon each other, form a re- 
markable subsidiary pair of jaws for propelling food down the esophagus: 
into the stomach. In all cases the teeth are merely Aaplodant, z.e:, they: 
are sharp conical points which sieze prey but are not used for mastication, 
The stomach is large and bent onitself. It is continued into a duodenum, 
at the commencement of which there opens a number of long czecal tubes 
called the pyloric ceca. They are said to secrete a digestive juice and. 
have been compared tentatively to a pancreas. The /ver is a large bi-; 
lobed organ with a gall-bladder from ‘which thére passes a single bile-’ 
duct to open into the duodenum. The duodenum is continued into the 
ileum which is long and coiled and terminates in the anus. Its hind 
