234 



LECTURE IX. 



sac and the short pyloric portion is continued from its right side, as 

 in the Perch, the Scorpoena, the Gurnards, the Bull -heads, the Smelts, 

 the Angler, the Pike, the Lucio-perca, the Sword-fish, the Silurus, 

 the Herring, and Pilchard, the Conger, the Murcena, and the Polyp- 

 terus {Jig. 62). A transitional form, in which the pyloric end is 

 bent so abruptly upon the cardiac as to make the 

 ciBcal character of the latter doubtful, is presented 

 by the short and capacious stomach of the Bur- 

 bot, the Blenny, and the Gymnotus. In the Mor- 

 myrus the stomach presents the rare form of a 

 globular sac {fig. 63. e). Where the ccecal cha- 



Stomach and pancreas ; 

 Polypterus. 



Stomach and pancreas ; 

 Mormyrus. 



racter is well marked the 



length of the blind end of 



the cardia varies consider- 

 ably ; in the- Polypterus, 



Conger, and Swordfish it 



forms almost the whole of 



the elongated stomach, the 

 short pyloric portion being continued from near its commencement ; in 

 tlie equally elongated stomach of the Pike, the pyloric portion is conti- 

 nued from the cardiac sac at a little distance from its blind end ; the 

 Herring, Gurnard, and Scorpa3na show an intermediate position of the 

 pyloric portion, and this is usually attended with a shorter and wider 

 form of the cardiac ccecum. The pyloric portion is usually slender 

 and conical ; but it dilates into a wide sac in Sargus and Lophius ; 

 and forms a small oval pouch in Trachypterus. In certain fishes the 

 stomach deviates from the typical forms either into the extreme of 

 simplicity or the converse, without, however, attaining in any species 

 that degree of complexity which we shall find in the higher organised 

 Vertebrata. A proper gastric compartment of the alimentary canal 

 cannot be said to exist in the Lancelet ; the long caecum {fig. 46. hd, 

 I) continued from it just beyond the cardia appears to be a simple 

 form of liver. In the higher Dermopteri, as the Sand-prides, the 

 Myxines, and the Lampreys, as also in Cobitis and Lepidosiren, the 

 stomach is continued straight from the oesophagus to the intes- 

 tine. I have found the capacious cai'diac division of the stomach 

 of the Lophius partially divided into two sacs ; the unusually wide 

 and short pyloric portion forming a third sac : there may also be ob- 

 served a few obtuse processes from the inner side of the cardia in this 

 fish. In the Gillaroo Trout the ascending or pyloric half of the bent 

 or siphonal stomach has its muscular parietes unusually thickened, 

 by which it is enabled to bruise the shells of the small fluviatile testa- 

 ceans that abound in the streams in wliich this variety of trout is 



