RHINODON TYPICUS. 



which are taken into the mouth and pharynx with the sea water which is 

 required for the purifying of the blood, is to be inferred from the branchial 

 openings being so guarded. That the fringe at the inner extremity of the 

 tubes, which exist in the branchial canals, are for the purpose of intercepting 

 such small animals as may be contained in the water, I infer from knowing 

 that the whale (Balcena), which feeds on small mollusca, &c, has the inner 

 edge of each layer of whalebone converted into a fine floating fringe, which 

 permits the water taken into its huge mouth to escape, but intercepts all 

 objects adapted for its food. 



When our shark proceeds to feed, the first step it probably takes is to 

 open its jaws to their full extent, in order to permit the mouth and pharynx 

 to become filled with sea water. On that being accomplished, the jaws are 

 then probably closed, in order that the water shall, by muscular efforts in the 

 pharynx, be propelled through the tubes in the branchiae, and forced thus to 

 leave behind it whatever mollusca, &c, it may chance to contain. The powers 

 of deglutition after this are probably called into action, and the oesophagus, 

 no doubt, is raised and straightened, so as to offer a ready passage downwards 

 to whatever shall have been collected during the escape of the water. The 

 mammillary eminences around the cardiac orifice of the stomach appear to 

 indicate that some, at least, of the articles of food are swallowed alive, and that 

 they require to be bruised, and also prevented from re-entering the oesophagus, 

 both of which are probably effected by the processes just mentioned. The 

 direction taken by the upper part of the oesophagus is evidently for the pur- 

 pose of enabling it the more effectively to resist the entrance of the water, 

 when being expelled through the branchiae by the muscular contraction of the 

 pharynx. 



The specimen described was the only one that had been seen at the Cape within the memory 

 of any of the fishermen. At the time it was discovered, it was swimming leisurely near the 

 surface of the water, and with a certain portion of the back above it. When approached, it 

 manifested no great degree of fear, and it was not before a harpoon was lodged in its body that 

 it altered its course and quickened its pace. 



The prepared specimen is deposited in the museum of the Jardin des Plantes of Paris. 



