2 THE LOWER FUNGI— PHYCOMYCETES 



serve as a basis for discussion. Names included in parentheses 

 are regarded here as synonyms. 



Thallophyta 



1. Myxothallophyta (slime thallophytes) 



A. Acrasieae 



B. Labyrinthuleae 



C. Myxomycetes (Mycetozoa, slime moulds) 



1. Exosporeae, i.e., Ceratiomyxa 



2. Endosporeae (Myxogastres) 

 II. Euthallophyta 



A. Bacteria (Schizomycetes, fission fvmgi) 



B. Fungi (Eumycetes) 



1. Phj-comycetes (lower fungi) 



2. Ascomycetes 



3. Basidiomycetes 



4. Fungi Imperfecti 



C. Lichens (Lichenes) 



D. Algae 



1. Cyanophyceae (Schizophyceae, blue-green algae, fission algae) 



2. Chlorophyceae (green algae) 



3. Phaeophyceae (brown algae) 



4. Rhodophyceae (red algae) 



The green coloring matter, chlorophyll, which occurs in practi- 

 cally all higher plants, is absent in several of the groups of the 

 Thallophyta. It is present in at least the majority of the algae, 

 and in a restricted sense perhaps may be said to occur in the 

 lichens. It is wholly absent in the Myxothallophyta, bacteria, 

 and fungi. 



In the presence of sunhght, plants containing chlorophyll 

 are able to synthesize the carbohydrates necessary to their metab- 

 olism from the carbon dioxide of the air and from water. Forms 

 of life lacking it are dependent on green plants for the elabora- 

 tion of their carbohydrate food. All non-chlorophyll containing 

 organisms (animals, slime thallophytes, bacteria, fungi) must 

 lead, consequently, a dependent existence, either as parasites 

 in hving plants or animals, or as saprophytes in dead or dis- 

 organizing plant or animal remains. 



Algae. — In their possession of chlorophyll and in their con- 

 sequent ability to lead an independent existence the algae are 

 strikingly different from the colorless thallophytes. It may be 

 assumed that they represent the primitive type from which the 

 higher green plants arose. In the morphology of the thallus 

 and organs of reproduction the group exhibits great diversity. 



