NOTES ON MEDIAN AND PAIRED FINS OF FISH. 



333 



Notes on the Development, Structure, and Origin 

 of the Median and Paired Fins of Fish. 



By 

 Edwin S. Cioodi'icli, F.R.S., 



Fellow of Mertoii College, Oxford. 



Willi Plates 10— U. 



Contents. 



Introduction 



The Lateral Fold Theory 



The Gill-arch Theory . 



Objections to the Gill-arch Theory 



The Apparent Migration of Fins . 



The Faithfulness of Muscle and Nerve 



The Shifting of Limbs Explained 

 Observations on the Structure anb Development of the 

 OF Elasmobranchs .... 



Development of the Median Fins of Scy Ilium canieula 



Development of the Skeleton of the Median Fins 



Development of the Paired Fins . 



The Concordance between the Muscles and the Radials 



Concentration 



The Fusion of the Muscle-buds 



The Position of the Fins 

 On the Nerve Supply of the Fins 



The Plexus of the Dorsal Fins 



On the Real Nature of the Nerve-plexus 



Experiments on the Nerve Supply of the Fins 

 Summary and Conclusion . 



Fins 



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VOL. 50, PART 2. NEW SERIES. 



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