548 THE PATHOGENIC ALGAE. 



The true Algae may be grouped as follows : (1) Conjugatae ; 

 (2) Chlorophyceae ; (3) Rhodophyceae ; (4) Phaeophyceae ; - (5) 

 CJiaraceae. 



Of these the Characeae includes no endophytes, the Conjugatae, 

 Phaeophyceae, and Rhodophyceae only species endophytic in other 

 algae or in animals. The Chlorophyceae, however, include a 

 large number of species which live as " aerial algae " endophytic 

 in Phanerogams, either as shelter-parasites or as true parasites. 



I. CHLOROPHYCEAE. 



These are divided into three groups : ^ 



1. Protococcoideae including the families Volvocaceae, Tetra- 

 sporaceae, Chlorosphaeraceae, Pleurococcaceae, Protococcaceae {Endos- 

 phaeraceac, Characieae, Sciadiaceae), and Hydrodictyaceae. 



2. Confervoideae including the families Ulvaceae, Ulothrichaeeae, 

 Chaetophoraceae Mycoideaceae, Cylindrocapsaceae, Oedogoniaceae, 

 Coleochaetaceae, Cladophm-aceae, Gomontiaceae, and Sphaeropleaceae. 



3. Siphoneae including the families Botrydiaceae, Phyllo- 

 siphonaceae, Derbesiaceae, Vaucheriaceae, Bryopsidaceae, Cauler- 

 paceae, Codiacecte, Valoniaceae and Dasycladaceae. 



Chlorosphaeraceae. 



Chlorosphaera endophyta Klebs. This is found between 

 the Hving epidermal cells of Lemna minor, and produces there 

 spherical cell-masses visible to the naked eye as wart-like 

 swellings. According to Prank, this is related to Bndoclmiium 

 polymorphum Prank. 



Entophysa charae Mob. This lives under the cuticle of 

 the epidermal cell-wall of Chara Hor-nemanni in Brazil. 



Endosphaeraceae. 



Most of the species can penetrate into living organs, but they 

 may also live as saprophytes or vegetate as independent organ- 

 isms. That all the Endosphaei'aceae are injurious to their host 

 has not as yet been proved. 



Chlorochytrium includes eight European species all endophytic 

 in living plants. 



' The arrangement used by Wille in Engler-Prantl. natur. Pflamzen-famiUen. 



