EXPLANATION OF PLATE 



PLATE 42 



Figures 1, 2, 5, 6, 7, 8, 10, and 11 were drawn by Dr. Helen M. Gilkey, and 

 the others by Miss Almeda H. Nordyke, under the direction of the author. 



Andbaena propinqua Setchell & Gardner 



Fig. 1. A group of plants. A, Young plants, the others are fruiting plants, 

 showing extremes in the variation in shapes of spores. X 500. 



Hormiscia sphaerulifera Setchell & Gardner 



Fig. 2. A, Basal portion of filament showing intramatrical rhizoids. B, 

 Vegetative cells in the median portion of the filament. C, An empty sporangium. 

 X 25. 



Hormiscia grandis (Kylin) Setchell & Gardner 



Fig. 3. A, Basal portion of filament showing numerous intramatrical rhizoids. 

 B, Two zoosporangia of moderate size. C, A long typical zoosporangium, empty. 

 T), Moderate sized vegetative segments. X 80. 



Hormiscia penicilliformis (Both) Fries 

 Fig. 4. A, Sporeling with rhizoid penetrating a filament of Ulothrix facca. 



B, Basal portion of a young filament, showing a few intramatrical rhizoids. 



C, Characteristic zoosporangia. D, Young vegetative segments. No description 

 is given of this species. X 80. 



Bhizoclonium lubricum Setchell & Gardner 

 Fig. 5. A, Terminal portion of a young filament with short segments. B. 

 Terminal portion of a filament with long, "resting" segments. X 160. 



ZJlothrix pseudoflacca f. maxima Setchell & Gardner 

 Fig. 6. A, B, Vegetative filaments. C, Sporangia. X 250. 



Codium dimorpJium Svedelius 

 Fig. 7. A young utricle with an empty sporangium. X 80. 

 Fig. 8. A terminal portion of a utricle, showing the extremely thick, lamel- 

 late and tuberculate end wall. X 100. 



Codium adhaerens M. A. Howe 



Fig. 9. Portion of the end wall of a utricle, showing internal modifications. 

 X 100. 



Codium Setchellii Gardner 



Fig. 10. Typical utricle and sporangium, showing also the scars of three 

 pervious sporangia. X 80. 



Fig. 11. Showing diff"erent forms of utricles and sporangia. 



[496] 



