314 



GEORGE WAGNER. 



Tornier, by an ingeniously chosen cut, separated the upper 

 one quarter or so of the Anlagen of both hind limbs in Pelobates. 

 The result was in several cases, at least, the formation of the 



FIG. i. 



normal pairs of limbs plus two complete extra girdles each with 

 a pair of limbs. Less completely successful experiments resulted 

 in fewer and less fully formed supernumerary parts. But the 

 monstrosities in all cases resembled closely those found in nature, 

 and the close approximation and exposed situation of the Anlagen 

 of the two hind limbs make accidents in nature which may be 

 compared with this artificial "accident" at least not improbable. 

 Tornier 's work, it seems to me, gives us a very satisfactory 

 explanation of such forms. 



Is it equally applicable to the forelimbs? The location of the 

 Anlagen under the opercle makes experimentation here much 

 more difficult, and no such experiments have been carried out, 



