Marble Groves and Gardens 135 



adv^erse situations, flourishing under the most unfavor- 

 able conditions known to chlorophyll-containing plants, 

 they have, nevertheless, reached the highest develop- 

 ment of all marine alga?. This is marked by their mode 

 of reproduction. Now this is an extremely complex 

 affair, and differs quite extensively in detail among the 

 different members of the group. In fact, so involved, 

 or modified, is it in some instances that it is as yet 

 poorly understood, even by professed botanists. Still, 

 I think that I can give some representation of the 

 process as drawn from a very simple case, that will 

 enable the reader to form at least a fair, if not com- 

 plete, conception of its general nature. 



Red algae are peculiar and unlike other algae from 

 the fact that they produce no swimming spores. Their 

 reproduction is carried out in two ways. These are 

 termed asexual reproduction and sexual reproduction. 

 In asexual reproduction, the spores are formed in an 

 envelope which, with its contained products, is called 

 a sporangium. Since the sporangium usually, but not 

 invariably, carries four of these spores, they are termed 

 tetraspores. These upon being discharged in the 

 water settle to the bottom and immediately start to 

 germinate and produce new plants. It will be noted 

 here that this method is quite different from that pre- 

 vailing in the spores of Fucus. There is no fusion of 

 cells prior to the development of the plants. This is 

 the usual way in which red algae multiply. 



But there sometimes occur in the life of a plant 

 extraordinary circumstances, somewhat like the winter 

 season or other unfavorable periods experienced by 

 land plants; and these unfavorable conditions must be 



