MAEDTE BOTANY. 85 



LXXXIX. Rhizogonium. Name derived from the root-like 

 form of the branches. 



1. Ripariunij river-bank rhizogonium. 



XC. Conferva. Name from confer ru?ni?iare, to consolidate. 



1. Arenicola, sand-growing conferva. 



2. Arenosa, sandy. 



3. Lettorea, sea-shore. 



4. Linum, flax. 



5. Sutoria, stitch-like. 



6. Tortuosa, twisted. 



7. Implexa, plaited. 



8. Melagonum, dark offspring. 



9. JErea, sand-loving. 



10. CoUabens, prostrate. 



11. Batigioides, the Bangor. 



12. Youngana, the Young. 



Family XX.— Ulvacejs. 



Plants growing in the sea, of a membranaceous substance, 

 and imperfectly reticulated structure. 



Frond, remarkably thin, either a tubular, or flat-filiform, 

 or expanded membrane ; colourless, or, owing to the pre- 

 sence of fructification, of a green or purple, (rarely) pinkish 

 colour. 



Fructification, minute green or purple granules, scattered 

 through the frond, or arranged in fours. — Harvey. 



XCI. Porphyra. Purple, from the colour of most of the 

 species. 



1. Laciniata, cleft porphyra. 



2. Vulgaris, common. 



3. Miniata, red tinted. 



