KNOWLEDGE OF CRYPTOGAMOUS PLANTS. 255 



The process of fructification has hitherto been observed with certainty' 

 by Karsteu in the Coenogonium ow\y. 



The excellent works of Elias Pries and Wallroth, which date back to 

 the sway of Linne's system, are still of great importance for purposes 

 of classification. Von Flotow has indirectly exerted great influence on 

 the study of lichens. His most prominent scholar, Korber, has inaugu- 

 rated a great reform in his two principal works, the Lichcnes Gcrmanuc 

 and the Parergis Uchenologicis. He created a new system, resting upon 

 an anatomical and organographic basis, and made more natural and 

 sharply defined subdivisions. He was ably assisted in his work by our 

 compatriot Massalongo, whose tables are unfortunately incorrect. The 

 works of Mylander are of great value ; his SgnopsiH Liclienum comprises 

 all known species. Its publication is still continued. Hepp did much 

 to make the European species known by the description of his collec- 

 tions and the investigation of their spores. Finally, we must not pass 

 over the works of Krempelhuber, wliic^h are at present confined to do- 

 mestic species ; but this excellent scholar will soon have a more exten- 

 sive field of operation. 



We now come to the largest and most interesting, but at the same 

 time the most difficult class of cryptogams — the fungi. Their sudden 

 appearance and growth, their ephemeral nature, and the multiplicity of 

 their forms, have always been a source of trouble to investigators, and 

 even the most indefatigable of modern mycologists have been able to 

 lift but partmlly the veil which hangs over the life and development of 

 these organisms. 



Far ahead of its time in organography stands the work of Professor 

 linger, on the exanthema of plants ; for in it we find the first attempt 

 to describe the development of mildew-fungi. Although the leading 

 idea of the whole work, that these fungi were the diseased products of 

 the plants on which they are found, was not confirmed, the rich treasure 

 of new facts laid down in this beautiful work retains its full value. 

 Corda, another fellow-countryman, has also written on fungi, and dis- 

 covered many interesting forms in the fungi of mold. He was thus 

 enabled to gain some insight into the life and development of these 

 organisms. In his princijial work, the Iconcs Fungorum, he represents 

 all forms of fungi known to him ; but some of his observations have 

 unfortunately been hastily made and consequently inaccurate. But we 

 should not forget that Corda lived in unfavorable external circumstances; 

 that for along time he had not the means of procuring a microscope, and 

 that he finally met with a tragical death. The ship in which he had 

 gone to Texas in 1849 foundered on his return voyage to Euroi)e, and 

 nothing has been heard of him since. The works of the Tulasne "broth- 

 ers throw new light on many chapters of this branch of study. They 

 show that there exists a great difference between the fungi of mildew 

 and those of mold ; that in the former not only spermogonia, but also 

 spores of different forms are produced, which had formerly been dis- 



