60 KEY TO NATURAL ORDERS 
petals of other flowers. The class includes grasses and sedges, These 
are not included in this work. 
Orpen IV—SPATHIFLORAE—Spap1x-FLOWERED PLANTS 
(Page 109) 
Flowers are borne on a fleshy, club-like receptacle (a spadix), which 
is usually surrounded by a broad leaf-like sheath, sometimes highly 
colored (A spathe). 
17. Calla. 18. Arisaema. 19. Acorus. 20. Orontium. 21. Peltandra. 
OrpER V—FARINOSAE—PLANTS wiTH MEALY SEEDS 
(Page 112) 
Flowers regular or nearly so (except in Commelina), the several 
earpels united into a single ovary. The flower parts are mostly in 
3’s or 6’s. Ovary situated above the corolla and calyx. Differs struc- 
turally from the following order in that the embryo is placed at the 
end of the seed opposite the point of attachment of the seed to the 
ovary. 
22. 23. 
25. 
22. Xyris. 23. Pipewort. 24. Day-flower. 25. Spiderwort. 
OrpvER VI—LILIFLORAE—Prants with Liniacrous FLOWERS 
(Page 117) 
Flowers generally conspicuous and symmetrical. The flower parts 
always in 3’s; petals 6, stamens 6 or 8, pistil 1 with a 3-celled ovary. 
26. 27. 28. 20. 30.) 13% Bz. 
33- 
26. Lily, 27. Onion. 28. Veratrum. 29. Bellwort. 30. Hyacinth, 31, False Lily- 
of-the-Valley. 32. Trillium. 33. Smilax. 
OrpeR VII—ORCHIDACEAE—PLANTS WITH ORCHIDACEOUS FLOWERS 
(Page 146) 
Leaves with parallel veins or veins spreading in elliptical lines. 
Flowers usually unsymmetrical, stamens growing in union with the 
pistil within the flower envelope. 
34- 35- 36. 37: 38. 39 40, 
34. Cypripedium. 35. Orchis spectabilis. 36. Orchis orbicularis. 37. White bog 
orchis. 38. Fringed orchis. 39. Pogonia. 40. Calypso. 
