10 SPRING FLORA OF MANHATTAN. 



flowered, mostly several aad erect. PerigyMium short, smooth, scarcely 

 nerved, beak short and entire Swampy land. 



C. tetanica, Schk. Staminate spike one; pistillate spikes 1-3, short, 

 more or less stalked. Perigynium nerved, smootli, the very short beak 

 bent to one side. Prairie, common. Leaf below lowermost spike 

 several cm. long. 



C. Pennsylvanica, Lim. The habit of tlie preceding but perigynium 

 pubescent, beak longer and toothed, and lower leaf only a little longer 

 than spike. Prairie, common. 



g 2. The two kinds of flowers in the s:ime spike. Spises short, 

 sessile and collected at the summit of stem. L^n•igynium plano-convex 

 and achene lenticular. 



C. Muhlenberg a, Schk. Staminate flowers borne at top of spike, 

 hence lower scales fruitful Per-gynia strongly spr^-ading at maturity. 

 Spikes close together, so as to form an aggregate spike- ike head. 

 Prairie, common. 



C. stmminea, var. fe.^tnc((ce'i. ( VVilld. ) Tuckerm. Stamuiate floweis at 

 base of spike, hence several of the lower scales empty causing the spike 

 to taper below. Perigvnia ascending Spikes usually 4-6, shortly 

 separated from each other. Common on prairie 

 3. ARACEAE. 



Flowers sessile, crowded on a fleshy axis (spadix). Fruit a lierry. 

 ARIS/EMA, Mart. 



Flowers naked, covering only the lower portion of the spadix, the 

 latter surrounded by a rolled up leaf or spathe Perennial from a corm. 

 Leaves compound. Fruit scarlet, l-few seeded. 



A. Dmcontium, (L.) Schott. Usually one leaf with several leaflets. 

 Spadix tapering into a long slender point which is exerted from the 

 rolled up tip of the spat'ne. Low vvoods, frequent, 



A friphjillum J L.) Ton: Leaves 2, each with B elliptical leaflets. 

 Spadices dioecious, club-sh iped and obtuse a!)Ove, shorter tluri the 

 hooded sfiathe. Rich woods, rare. 



4. COMMELINACEAE. 



Calyx of 3 green sepals. Corolla of 3 colored petals whicli soon 

 wither. Stamens 6. Ovary 2-3-celled, free. Fruit a capsule. 

 TRADESCANTIA, L. 



Petals pink or violet. Filaments covered with long violet hairs. 

 Flowers umbelled in terminal and axillary clusters. 



T. VirglrUaaa. L Common in low prairie. Flowers opening on 

 sunny mornings and soon withering. 



5. JUNCACEAE 



Perianth of (> similar, persistent, bract-like divisions Stamens (>. 

 Ovary one, superior, 3-carpelled. Style 1, stigmas 3. Fruit a 3 valved 

 capsule. Grass-like herbs 



JUNCUS, L 



./. tpnni.^, Willd. Stem wiry, 2-4 dm. high. Flowers small, green. 



