No. VI.] 



NOTICES OF THE FISHES. 



719 



The oesophagus is short and muscular, and its lining has a glandular appearance. 

 The intestinal canal, from pharynx to anus, makes four convolutions and a half, and 

 bears a proportion to the length of the fish, excluding the caudal fin, of 50 to 

 18, or 2.8 to I, The proportions, however, vary somewhat in different individuals. 

 The upper part of the canal, answering to the stomach, has a greater diameter; 

 at the first turn it suddenly undergoes a small contraction, by which a minute sac is 

 formed on one side of the canal only. From this contraction to the anus, the diameter 

 of the intestinal canal, and the strength of its coat, diminishes gradually. Its inner 

 membrane is disposed throughout in minute and delicate rugse, which have a longi- 

 tudinal direction, but are indented and waved into each other in a very beautiful 

 manner. There are no case a. 



The lobes of the liver are numerous, and so intermixed with the folds of the 

 gut, that it is difficult to separate them entire. It has a pale colour. The gall 

 bladder lies betwixt the intestines and air bladder. Its duct opens into the upper 

 part of the stomach, immediately behind the septum of the thorax. The bile is 

 pale. 



The spleen is large, and lies in a semicircular form round the upper part of the 

 exterior convolution of the intestine. 



The air bladder extends the whole length of the abdomen, and consists of two 

 portions, united by a very short tube. The upper portion is shorter, and is furnished 

 with a remarkably thick shining white capsule, which adheres strongly at its upper 

 end to the spine and septum ; a very slight degree of force suffices to thrust the 

 bladder out of the capsule. The true coats of both portions are firm, and less 

 readily torn than the above-mentioned capsule, but are much thinner. A small tube 

 for discharging the air proceeds from the upper end of the lower portion of the 

 bladder. 



The kidneys extend the whole length of the abdomen, and are connected with each 

 other, immediately below the diaphragm, by a transverse lobe. The urinary bladder 

 is a long tube, whose width scarcely exceeds the joint diameters of the ureters. 



The lining of the abdomen is white. The intestines are attached on every side to 

 the parietes of the abdomen, by numerous processes of the peritonaeum. 



The intestines are infested by small worms, which fix themselves to their inner 

 coats by a kind of proboscis. 



Fins. — The pectoral fins are elliptical, and are four times and a half shorter than 

 the body of the fish, estimated from the setting on of the head to the base of the 

 caudal fin. The dorsal fin is rhomboidal ; its first ray is short, the next about two 

 inches long, the posterior ones gradually become a little shorter ; the last one is 

 nearly bipartite ; their numbers vary from twelve to fourteen. The ventrals are 

 situated opposite to the dorsal, are rather small, and have an obtuse unequal obovate 



