CHEMICAL HEREDITY 



Biogenetical Law of Haeckel extends to chemical 

 phenomena. We know that the embryos of higher 

 animals show considerable morphological re- 

 semblances to lower animals, and so it is in plants. 

 The first stages of development in mosses resemble 

 algae, the first development of ferns reminds us 

 very strongly of liverworts. These facts are so 

 general that they have been summarised in the 

 rule : That the development of the individual 

 organism or the ontogeny represents a short re- 

 capitulation of the phytogeny. This law is hitherto 

 only based upon morphological facts. Since 

 morphological phenomena are always accom- 

 panied by chemical analogies, we may suppose 

 that the law of Biogenetics can be applied also to 

 chemical phenomena in life. Many reasons can 

 be produced to support this idea. The primitive 

 groups of higher plants, such as Mosses and Ferns, 

 and Gymnosperms, do not contain by far as 

 many different substances as the Phanerogams. 

 All the numerous glycosides, most alkaloids, and 

 the bitter principles occur in the phanerogamic 

 groups. The lowest plants of the classes Algae 

 and Fungi in general contain only the wide- 

 spread organic compounds, such as fats, carbo- 

 hydrates, or proteids. The Lichens, a highly 

 developed symbiotic group of Fungi, alone contain 

 a greater number of specific organic compounds 

 belonging to the class of benzene-derivatives. 

 The lowest Algae and Fungi as well as the Bacteria 

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