268 Examination of the Matured Framework [Book ir. 



generally hitting on the correct, or at least the correcter view. 

 For instance, Rudolphi denies altogether the vegetable nature 

 of Fungi and Lichens, because he finds no resemblance 

 between their hyphae and vegetable cell-tissue, and he supposes 

 them to arise by spontaneous generation ; even of the Confervae 

 he says that the microscope has shown him nothing that agrees 

 with the structure of plants, — evidently a sign of bad observa- 

 tion or of incapacity to understand what he saw. Link on the 

 other hand regards all Thallophytes as plants, and sees that 

 the filaments of Lichens and Fungi consist of cells, and that 

 cells occur at least in many Algae. Rudolphi praises in the 

 same breath the views of Wolff and Sprengel on cell-tissue, 

 although they are directly opposed to one another, and although 

 he adopts Sprengel's strange theory of cell-formation without 

 alteration. Link on the contrary declares against Sprengel's 

 theory, and on good grounds, and shows that the vesicles 

 which Sprengel took for young cells are starch-grains ; at the 

 same time he makes new cells be formed between the old ones. 

 Rudolphi is of opinion that cells open into one another, as is 

 plainly shown by the passage of coloured fluids. Link main- 

 tains that cells are closed bodies, and proves it well by the 

 occurrence of cells with coloured juice in the middle of colour- 

 less tissue. Rudolphi represents the orifices of the stomata as 

 encircled by a roundish rim, which he takes without hesitation 

 for a closing muscle because the apertures enlarge and diminish. 



details, and was held in estimation by many chiefly as a good teacher and 

 philosophic author of popular works on natural science. He was one of 

 the few German botanists in the early part of the present century who 

 aimed at a general knowledge of plants, and combined anatomical and 

 physiological enquiries with solid researches in systematic botany. Of his 

 many treatises on all branches of botanical science, zoology, physics, 

 chemistry, and other subjects, his Gottingen prize essay must be considered 

 to have contributed most to the advancement of science. Von Martins 

 somewhat overrates his scientific importance in his ' Denkrede auf H. F. 

 Link' in the ' Gelehrte Anzeigen,' Miinchen (185 1), 58-69. 



