THE GREEN ALGiE 



99 



present day generally grouped together as Isokontae, one of 

 the groups that has emerged from the old class of the Chloro- 

 phyceae. The establishment of this group dates from the 

 definite recognition of the Flagellate ancestry of the Algae 

 (Bohlin 9, Blackman 5). All the different genera considered in 



Protomastigineae 



/ 

 / 



Cryptomonadineas 



Polytomacete 



Volvocaceae 



Polyblepharidaceas 

 Chlorodendraceas 



Chloromonadineae 

 \ 



\ 

 Heterokonts 



TetrasporaceiE 



Chlorella- 



Chlamydomonadaceee 



? 



Mesotccniaces 



Desmidiace^e- 



Zygnemaceai Chloyochytrium 

 / 



Chytridineae 



Protococcacere 



-Scenedesmacese 



Protosiphon 



Ereinosp/i<£ra 

 CJilorosphara 



Cladophoracese 

 Ulotrichales 



\. ^^Chroolepideje 

 Cylindrocapsa 

 ? 



Siphonocladeje 

 Vii/u'//cr/(i (^Dcrbcsia) 

 Hydrodictyaceaj Siplioneae Archegoniatai 



Phycomycetcs 

 Table showing probable relationships of the different groups of the Green Algze 



Qidogoniacene 

 (Stephanokontaj) 



the preceding pages are therefore supposed to arise directly 

 or indirectly from a Flagellate group, having two (or four) cilia 

 of equal length, green chloroplasts with pyrenoids and starch 

 as the first visible product of assimilation. In the preceding 

 pages we have endeavoured to trace back all the diverse series 

 of the Isokontai to a Chlamydomonad ancestry, and the Chlamy- 



