i8 Transactions British Mycological Society. 



of a much more generalised type than marine forms at present 

 existing. This is an interesting speculation, but it is not more 

 than a speculation, and even if an agnostic attitude be adopted 

 in regard to it, most mycologists will combat the idea that the 

 fungi, thus derived, possess little or no novelty in form- 

 development. 



Although Church's view that fungi have arisen from trans- 

 migrant algae is unsatisfying, even more problematical is the 

 outlook, still prevalent among botanists, that the fungi have 

 been derived from algal forms somewhat similar to existing 

 types of Green and Red Algae. This is a reflection of the views 

 of Pringsheim, de Bary, and Sachs, especially of the last named. 

 It may be remembered that Pringsheim actually placed Sapro- 

 legnia amongst the green algae, as a colourless form. Since the 

 lifetime of these botanists, however, further research has thrown 

 a flood of new light upon the fungi, which makes much more 

 problematical the correctness of their views. It is a common- 

 place of botanical lecturers to compare Pythium with Vaucheria, 

 and Mucor with Spirogyra, and the comparison is not in- 

 frequently accompanied by more than a suggestion that the 

 forms may be phylogenetically connected. Again, the Ascomy- 

 cetes and the Rust Fungi are commonly connected with the 

 Red Algae, in the main, apparently on account of the presence 

 of trichogynes and spermatia. In my opinion the resemblances 

 between these groups of algae and fungi are entirely superficial, 

 and are of no phylogenetic significance whatever. If the com- 

 parison is pressed for instance between Pythium and Vaucheria, 

 enormous differences are found between the two forms; for 

 instance the mode of germination of the zygote, a character 

 probably of considerable ancestral importance, is different, and 

 the characters of the ciliated cells are so diverse that a phylo- 

 genetic connection seems out of the question*. It is even more 

 difficult to conceive of a phylogenetic comparison being drawn 

 between Mucor and Spirogyra, and the sooner such is relegated 

 to the limbo of forgotten things, the better for botanical clarity 

 of vision. As between the Ascomycetes and the Uredineae on 

 the one hand, and the Red Algae on the other, the comparison 

 is usually of a more delicate nature, but it seems equally 

 fallacious. The comparison between the trichogynes of the 

 respective groups can hardly be taken seriously for there are 

 great structural differences between them, while in sexuality 



* Since delivering this address, Dr Butler has reminded me of his paper 

 " On A lloniyces, anew aquatic fungus" (Annals of Botany, xxv, p. 1123, (1911), 

 in which this curious genus of the Leptomitaceae is compared with the algal 

 genus Dichotomosiphon . Although the resemblance between the growth forms 

 of these two genera is striking, the profound differences in reproduction appear 

 to me to invalidate any phylogenetic connection between them. 



