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valueless in any but an aquatic environment. Liver- 

 worts and Mosses, which we take as instances of the 

 humbler land-plants, propagate as freely by vegetative 

 means as by the sexual mode. In them the aquatic 

 zoospore seems to be replaced by detachable buds, or 

 gemmae, which readily develop into new individuals. 



In the animal kingdom asexual reproduction, and also 

 regeneration of lost parts, are observed up to a certain 

 point. The fresh- water Hydra may be cut up into quite 

 a number of pieces, and each piece may reproduce the 

 parent form, and it is commonly known that this animal 

 produces buds which remain vitally attached to the 

 parent even after they are so far grown as to be able to 

 fend for themselves. Ultimately, however, they become 

 detached. Asexual reproduction is found from the 

 simplest animal forms up to the Sea-Squirts, or Tuni- 

 cates. Regeneration of lost parts, which, of course, 

 does not imply multiphcation, is weU Olustrated by 

 Crabs and Starfish; it also occurs in Lizards. Any of 

 these animals can regenerate a lost limb with a facility 

 which must be the envy of a man who has had an arm 

 or a leg amputated. Man and the higher animals have 

 lost a power of physical regeneration possessed by 

 humbler creatures; it is the price they have to pay for 

 complex organization. Yet even highly organized man 

 is not entirely destitute of regenerative capacity, for he 

 can replace a portion of skin or a finger-nail that he may 

 have lost. But if the capacity for reproduction of com- 

 plete individuals from parts of a parent form is arrested 

 at a certain point in the scale of animal life, it is hardly 

 so in plants. The capacity is exhibited, in a great 

 variety of ways, almost throughout the entire plant 



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