332 THE PLANT PHYLA 



Class 2. HOLOPLASTIDEAE. With nuclear menihrane. 

 (Sp. about 20.) 

 Order Glaucocystales. Dividing in one plane. 

 Family 16. Glaucocystaceae. — Glaucocystis. 



Phylum II. CHLOROPHYCEAE. Tlie Simple Algae 



Normally chloro])liyll-green, with well-developed single cells, 

 or filaments. (Here restricted to two 

 classes of green algae). 



Class 3. PROTOCOCCOIDEAE. Green Slimes. Unicellu- 

 lar. (Sp. about 450.) 

 Order Palmellales. Cells not in colonies. 



Family 1. Protococcaceae. No zoospores. — Proto- 



coccus, Trochiscia, Crucigenia. 

 Family 2. Chlorococcaceae. With zoospores. — Chloro- 



coccum, Tetraspora. Botryococcus. 

 Family 3. Synchytriaceae. Colorless parasites. — 

 Olpidium, Synchytrium. 

 Order Coenobiales. Cells in colonies. 



Family 4. Hydrodictyaceae. Vegetative cells not cili- 

 ated. — Scenedesmus, Hydrodictyon. 

 Family 5. Volvocaceae. Vegetative cells ciliated. — 

 Gonium, Pandorina, Volvox. (Ani- 

 mals!) 

 Class 4. CONFERVOIDEAE. Confervas. Filamentous, or 

 a plane. (Sp. about 640.) 

 Order Microsporales. Unbranched. 



Family 6. Microsporaceae. — Microspora. 

 Order Schizogoniales. Unbranched. 



Family 7. Prasiolaceae. — Prasiola. 

 Order Ulvales. Plant a plane or tube. 



Family 8. Ulvaceae. — Ulva, Enteromorpha. 

 Order Chaetophorales. Usually branched. Zoospores 

 and ciliated gametes. 

 Family 9. Ulotrichaceae. Unbranched. — Ulothrix. 

 Family 10. Chaetophoraceae. Branches attenuated 

 into hairs. — Draparnaldia, Chaeto- 

 phora. 

 Family 11. Alicrothamniaceae. Scarcely attenuated, 

 no hairs. — Microthamnion. 



