ORDER LXI. rMBELLIFER^E. 329 



4. Flower? yellow or Exeenish 5 



Flower* white or blue 7 



5. Leaves pinnately divided Daucus, 22 



Leaves tenutely divided 6 



- d nearly terete Thaspium, 13 



Hat on one side, convex on the other Zisia, 12 



mpressed 8 



uipressed 18 



-. Beads compressed on the sides 9 



is compressed on the back. 16 



9. Leaves 3- parted CryptotaniOy 11 



Leaves triternate or qainnate Oicuta, 8 



Leaves dissected, pinnate, or ternate 10 



10. Leaves bipinnate. segments pinnatifid ("luerophyllum, 23 



. pinnate, or ternate 11 



11. Leaves much dissected 15 



Leaves pinnate or ternate 12 



12. Leaves ternate 13 



Leaves pinnate 14 



13. Involucre none Heloscia'Hum, 5 



Involucre 2 — Heaved Neurophylk 



14. Involucre 1— "-leaved ffelosoiadium, 5 



Involucre 5 — G-leave.i 'iiuin, 9 



15. Involucre with parted leaflets Diseopleura, 6 



Involucre none Leptoca ulie, 7 



16. Leaves simple, terete Tiedmannia, 17 



Leaves compound 17 



17. Petioles inflated, 3-parted Arehangelica, 16 



Petioles simple Arduranra, 18 



18. Seeds linear Osmorhiza, 24 



Seeds ovate-oblong Liguiticum, 15 



Tribe L— HYDROCOTYLE'JE. 



Fruit laterally compressed. Seeds flat on the face. Vittce 

 2 or none. Umbels simple. 



Gents I.— HYDROCOT'YLE. Tourn. 5—2. 



(From the Greek hudor, water and cotule, a cavity, from the locality of the plants 

 in the water, and the cup-like appearance the leaves sometimes assume.) 



Margin of the calyx obsolete. Petals entire, ovate, acute. 

 Fruit flattened laterally, 5-ribbed. Herbaceous plants, aquatic, 

 creeping stems and peltate or cordate leaves. Flowers in sim- 

 ple umbels. Involucre 4-leaved. 



1. H. America'xa, (L.) Stem glabrous. Leaves orbicular, reniform, 

 slightly 7-lobed, crc-nate. Flowera few, sessile, i:i axillary umbels. — 

 White or greenish. 2f.. May — June. Mountains. 2 — 3 inches. 



2. H. inteerui' ta. (MuhL) Stem, terete, glabrous, creeping, branch- 

 iui:. Leaven peltate, orbicular, doubly crenate. Flower* in Bmall, 

 nearly sessile, capitate umbels, 4 — 8-flowered. Fruit broad. — White. 

 11. Through the summer. In wet soils. 3 — 4 inches. 



3. II. UMBUUTA. (L.) Stan glabrous, creeping or floating L 

 peltate, erenate, emarginate at the base. Umbel* many-floweredv on 

 long peduncles. Frail somewhat tumid. Calyx slightly toothed. — 



2J. Through the summer. Grows in bogs. 4: — 6 inches. 



