XVI TABULAR ARRANGEMENT OF NATURAL ORDERS. 



H. Embryo solid ; no albumen. Perigone coloured, superior. 



147. Burmanniacea (p. 605). Perigone symmetrical. Stamens 3. 



148. Orchidea (p. 606). Perigone asymmetrical. Fertile stamen 1, gynandrous ; pollen 



in masses. 



Crtptogamje vasculares. Propagation by simple cells (spores), impregnation by an- 

 theridia (not by pollen). 



149. Rhizocarpece (p. 644). Sporangia included in conceptacula. Aquatic herbs. 



150. Lycopodiacea (p. 645). Sporangia axillary. 



151. Equisetacece (p. 648). Sporangia at the under side of peltate scale3, the latter in 



terminal cones. 



152. Filices (p. 648). Sporangia in sori at the under side of the leaves. 



