21 



here. The main statement on which it reposes is that there is no 

 genetic connection between the Gonidia and the Hyphoe, a statement 

 which is not admitted by the Lichenists. 



While this controversy was going on, Dr. Minks, a young botanist 

 of Stettin, came forward with the results of long continued and close 

 observation, which if substantiated put an entirely new face on the 

 matter, and must profoundly affect the whole future of Lichenology. 

 Of his doctrine, contained chiefly in two elaborate works, Das 

 Mierogonidium and Symbolae LichenologicsB, we can only give a 

 short summary. He asserts firstly the existence of a very delicate 

 tissue called the Hyphema, which permeates all parts of Lichen- 

 structure, and is its primal basis ; secondly, that the Hyphse them- 

 selves contain Gonidia (Microgonidia) , and that these occur also in 

 the so-called spermatia, in the Hypothallus, in the spore ; in short, 

 that the Microgonidia occur in every part of the Lichen, and are the 

 test and evidence of its autonomous existence. In the second of the 

 works above mentioned, he has claimed that a large number of plants 

 mentioned by him, heretofore placed among Fungi, are really to be 

 considered as Lichens, because they exhibit Microgonidia in their 

 tissues. He has discovered new organs, the Gonangium, the Gono- 

 cystium, and the Hormospore, and has invented a new terminology 

 of most parts of Lichen structure, and has other doctrines, such as 

 the alternation of species, or something analogous to it, which he 

 has not yet fully developed. In view of his studies, it is certainly 

 too soon to say that the question is decided against the autonomy of 

 Lichens. It is, at least as yet, sub litem,, and to be decided by fur- 

 ther investigation, which belongs to the experienced botanist and 

 not to the beginner. For the present and for practical purposes the 

 Lichen remains a Lichen. The gonidial or algoid part has been" 

 classified by Schwendener and Th. M. Fries, but no one has as yet 

 undertaken to classify the Fungoid parasites on a Fungoid basis 

 except under the general designation of AscomycetEe. 



CHAPTER III. 



ON THE DISTKIBUTION OF NORTH AMERICAN LICHENS. 



The Lichen fiora of North America, extending, as it does, from 

 the Arctic to the tropical regions, from the Atlantic to the Pacific 

 gpast, including ranges of lofty mountains, and every variety of 



