252 Experimental Zoology 



with the result. Some experiments that I have carried out 

 disprove this suggestion also. The lungs of tadpoles about to 

 transform were removed at the base. The animals underwent 

 their normal metamorphosis, as when the lungs are present. Not 

 only was the tail absorbed, but the gills also. If the operculum 

 that covers the gills is removed so that the gills are exposed to 

 the water, they become absorbed at the proper time. How far 

 these changes are comparable with senescence remains to be 

 shown. 



LITERATURE, CHAPTER XV 



DAVENPORT, C. B. The R61e of Water in Growth. Proc. of the Boston 



Soc. of Natur. Hist. XXVIII. 1897. 

 Experimental Morphology, I. 1897. II. 1899. 

 FEHLING, H. Arch. f. Gynakologie, XI. 1877. 

 MINOT, C. S. Senescence and Rejuvenation. Jour, of Physiol. XII. 



1891. 

 MORGAN, T. H. The Origin of Species through Selection contrasted with 



their Origin through the Appearance of Definite Variations. Pop. 



Sci. Monthly. 1905. 



POTTS, R. Landwirth. Versuch-Stat. XXIII. 1879. 

 WEISMANN, A. Duration of Life, 1881. (Essays upon Heredity.) 



