28 



said, it has been clearly proven that the ascus fruit in general 

 originates asexually. Notwithstanding all this the author com- 

 plains of the exceeding obstinacy of those who still bring forward 

 the old argument and explain by bringing in apogamy and such 

 far-fetched analogies as the swarm-spores of Ectocarpus. 



For the benefit of those who still hold fast to the one strong 

 point in favor of the sexual theory, viz.: the facts in case of Col- 

 lema microphyllimt, he adds a single fact, which is that sperma- 

 tia of this plant, after lying one month in prepared food solution, 

 began to show signs of germination ; after two' and three months 

 they had thrown out tiny tubes in two or three directions, and 

 not till after the fourth month did the tubes reach the staee of 

 branching. It is therefore, the opinion of the author that when 

 the various kinds of lichen conidia (spermatia) have been studied 

 so as to allow of their arrangement in a series whose members 

 show a constantly decreasing power of intensity of growth, those 

 of Collema will stand at the end of this series, as up to the 

 present time they show the slowest growth of any forms inves- 



tig-ated. 



i> 



E. L. G. 



Culture of Licheti-building Ascomycetes without Algce : By 

 Alfred Moeller, and Germination of Lichen-spores on Moss-pro- 

 tonema and on Algce which are not like the Gonidia of the 

 Lichens: By Gaston Bonnier. 



In the Naturwissenschaftliche Rundschau of October 27 both 

 of these articles are reviewed, and the results of the experiments 

 given. The reviewer begins by stating that the so-called 

 Schwendenerish theory, as elucidated by him about 20 years ago, 

 in regard to the double nature of Lichens, for the majority of 

 botanists had passed out of the stage of theory into that of scien- 

 tific certainty, but that quite recently some few Lichenologists, 

 Stein, Nylander and others, had placed themselves on the oppo- 

 site side of the question. 



The theory can be proven either by synthesis or analysis. The 

 former method has been tried successfully by Rees, Treub and 

 Stahl, and still more recently by Bonnier, that is, the Lichen- 

 thallus has been raised by uniting fungus-hyph^e and certain 

 Algae forms. By the analytical method it must be proven that 

 the ereen part of the lichen, the <^c^.r-:,\\^A -.a-.^ „__ •j-.-.r-_i 



