224 THE SWIM-BLADDER OF FISHES 



15. Monro, Prof, Alex. Structure and Phj'siol. of Fishes. Edinburgh, 1785. 



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" Menioires de Physiol. Vol. 15. 



17. Packard, A. S. Zoology. 3rd. ed. New York, 1881.' 



18. Prince, E. E. Slat, Ann. Rep. Mar. and Fisheries, Ottawa, 1898. 



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20. Studler, Dr. M. T. Dev. of the Nose and Pharynx in Man. Amer. 

 Journ. of Anatomy, Vol. 1. Sept., 1902. 



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24. Tower, Prof. R. \Y, The Gas in the Swim Bladder of Fishes. Bulletin 

 U. S. F. Comm. XXI. 1901. 



25. Wright, Prof R Ramsay. Contributions to the Anatomy of Ameiurus. 

 Proc. Canad. Inst. Toronto, 1884. 



26. Wright, Prof. R. Ramsay. On the skull, &c., of the Siluroid Hypoph- 

 thalmus. Trans. Roy. Soc, Vol. III. 1885. 



LIST OF REFERENCE LETTERS IN THE PLATES. 

 a. anus mes. flattened mesoderm cells clothing 



bl. gall-bladder. the swim-bladder. 



b. b. bony expansions of vertebral 



processes. 

 com. cornua or anterior processes of 

 swim-bladder, 

 d. duct of swim-bladder. 

 do. opening of do do in oesophagus, 

 epith. large epithelial cells lining 

 developing swim -bladder. 

 go, genital opening. 

 ht. heart. 

 /. k. I. chain of ossicles from ear to 

 swim bladder. 

 int. intestine. 

 k. kidney. 

 I. liver. 



DESCRIPTION OF PLATES. 



Plate 20. 



Fig. 1. Haddock (Melanogrammiis cegle firms, Linn.) dissected to show the 

 ductless swim-bladder in -situ. 



Fig. 2. Perch (Perca jlavescens, Mitch.) dissected to show the ductless swim- 

 bladder with slightly bifid anterior end. 



Fig. 3. Herring {Clvpea hareitgus, Linn ) dissected to show the swim-bladder 

 with anterior process, the duct (d) opening into the stomach, and the 

 posterior opening (x) on the left of the anus (a). 



