CHAPTER VII. Phylogeny

PHYLOGENY

I. GENERAL STATEMENT

A. ORIGIN OF LICHENS 272

B. ALGAL ANCESTORS 273

C. FUNGAL ANCESTORS 273 a. Basidiolichens b. Ascolichens

II. THE REPRODUCTIVE ORGANS

A. THEORIES OF DESCENT IN ASCOLICHENS 273

B. RELATION OF LICHENS TO FUNGI 275 a. Pyrenocarpineae b. Coniocarpineae c. Graphidineae d. Cyclocarpineae

III. THE THALLUS

A. GENERAL OUTLINE OF DEVELOPMENT OF THALLUS 281 a. Preliminary considerations b. Course of evolution in Hymenolichens c. Course of evolution in Ascolichens

B. COMPARATIVE ANTIQUITY OF ALGAL SYMBIONTS 282

C. EVOLUTION OF PHYCOLICHENS 283 a. Gloeolichens b. Ephebaceae and Collemaceae c. Pyrenidiaceae d. Heppiaceae and Pannariaceae e. Peltigeraceae and Stictaceae

D. EVOLUTION OF ARCHILICHENS 287 a. Thallus of Pyrenocarpineae b. Thallus of Coniocarpineae c. Thallus of Graphidineae d. Thallus of Cyclocarpineae AA. LECIDEALES aa. Coenogoniaceae bb. Lecideaceae and Gyrophoraceae cc. Cladoniaceae 1. Origin of Cladonia 2. Evolution of the primary thallus 3. Evolution of the secondary thallus 4. Course of podetial development 5. Variation in Cladonia 6. Causes of variation 7. Podetial development and spore-dissemination 8. Pilophorus, Stereocaulon and Argopsis BB. LECANORALES aa. Course of Development bb. Lecanoraceae cc. Parmeliaceae dd. Usneaceae ee. Physciaceae