NOTE ON ALTERNATION OF GENERATIONS 

 AND PARTHENOGENESIS. 



THE theories of Spontaneous Generation, and of 

 the Progressive Development of animals from lower 

 to higher forms, wage open war with the great 

 truths of Theology, and, as altogether untenable, 

 seem now to be generally opposed by Naturalists. 

 The theories (or theory) of Alternate Generations and 

 Parthenogenesis do not maintain the same hostile 

 attitude to religion ; and the final decision regarding 

 them is accordingly of less importance. But they 

 present deep and difficult questions for the considera- 

 tion of the Naturalist, and seem destined for a time 

 to lead to much discussion and diversity of opinion. 



They certainly present to us new and strange 

 modes of reproduction of life. Trembley's researches 

 in connexion with the Hydra, gave the first intima- 

 tion of them, when, in 1744, he apprised the world 

 of its singular and manifold powers of reproduction. 

 " Imagine a lily producing a butterfly, and the 

 butterfly producing a lily, and you would scarcely 

 invent a marvel greater than the production of Me- 

 dusae was to its first discoverers. Nay, the marvel 

 must go farther still ; the lily must first produce a 

 whole bed of lilies like its own fair self, before giving 



