iv EXPERIMENTAL TERATOGENY 195 



producing monstrosities which are not of such a sort 

 as to prevent the continuation of life after the end of 

 the developmental period. We may expect that 

 many methods will be discovered through which the 

 embryo of most groups of animals and plants can 

 be modified in some degree, without impairing 

 vital functions, and this discovery will certainly prove 

 most beneficial to experimental transformism. Other 

 investigators have, in most parts of the scientific 

 world, followed M. C. Dareste's experiments, and the 

 results are valuable. For instance, M. J. Fallou l has 

 shown that when cocoons of Attacus Pernyi are hung 

 vertically, the butterflies are normal, while if resting 

 horizontally the same cocoons yield abnormal butter- 

 flies. He adds that a very slight disturbance in the 

 internal conditions of the mode of suspension is enough 

 to induce important variations. This point should 

 be investigated anew. Again, G. Pouchet and Chabry 

 have recently investigated the influence of some che- 

 mical conditions on the development of young sea- 

 urchins, by depriving the water in which the eggs are 

 hatched of one of its normal components, carbonate of 

 lime, 2 and they have seen that under such conditions 



1 Etude sur la Prod^lction Artificielle des Lepidopftres anormaux. 

 B^lll. Soc. Acclimatation, 1887, p. 499. 



2 Sur le Developpement des Larves d* Our sin dans FEau de mer 

 privee de Chaux. Comptes Rendusdela Societe de Biologic, 1889, p. 17. 



O 2, 



