UMBELLIFERiE. 253 



The genera arc difficult, as they have to rest mainly on the fruit and seed : these are Ixjst ex- 

 amined in transverse slices. The whole order is divided into numerous tribes. These, being 

 somewhat recondite, are here dispensed with. 



I. Umbels simple, or irregularly or imperfectly compound, the flowers .sessile or slightly pedi- 



cellate. Oil-tubes none or obscure. 



♦ Leaves simple, not strongly lobed nor toothed : umbels simple or proliferous : flowers white, 



without bracts : oil-tubfs none. 



1. Hydrocoty-le. Leaves peltate or orbicidar. Fruit rounded, laterally compressed, smooth : 



ribs fdiform. Creeping, aijuatic or subaqt\atic. 



2. Bowlesia. Ijcaves ronii'orm, opposite ! Fruit ovate, turgid and ribloss, pubescent. 



♦ * Loaves spinosely toothed, or palmatoly lobed or pinnatifid : oil-tubes obscure. 



3. Eryngium. Loaves rigid, spinosely toothoil. Flowers jiorfect, bracteato, sessile in dense 



heads, bluish. Fruit covered with hyaline scales. 

 4." Sanicula. Leaves lobed and incised. Flowers polygamous, in irregularly compound um- 

 bels, mostly yellow. Fruit covered with hooked j)rickles or tubercles. 



II. Umbels regularly compound. Fruit without prominent secondary ribs and not furnished 

 with hooked or barbed prickles. Oil-tubes rarely wanting. 



♦ Fruit more or less compressed laterally, broadly ovate or subglobo.so to elliptic-oblong, not 



broadly winged. 

 +- Seed terete, with involute margins : oil-tubes conspicuous : carpophore entire : flowers yellow. 



5. De'weya. Fruit oblong or nearly orbicular ; ribs filiform or prominent : oil-tulM!S 2 or 3 in 



the intervals. 



-f- +- Seed deeply sulcate on the face : oil-tulms wanting : carpophore 2-parted : flowers white. 



6. Conium. Fruit broadly ovate, with prominent equal obtuse ribs. 



-H -f- -H Seed nearly terete or but slightly concave on the face : flowers white. 



++ Fruit small, not prominently ribbed : oil-tubes solitary : stylopodium depressed : umbels 

 naked, sessile or nearly so. 



7. Apium. Fruit broadly ovate : seed not concave : carpophore entire. Biennial. 



8. Apiastrum. Fruit cordate : seed concave and longitudinally incurved : carpophore 2-partcil. 



Annual. 



++ ++ Fruit not prominently ribbed : stylopodium more or less jiromincnt : carjwphore bifid or 



2-parted. 



9. Carum. Fruit ovate or oblong ; ribs filiform : oil-tubes .solit<iry. Involucre and involucels 



usually pre.sont. Leaflets linear, entire. 



10. Plmplnelift. Fruit ovato, with a broad ronimissure ; ribs slightly proininont : oil-tulws 

 inimi^rouH. Unibols neiuiy naked. LeallclH cunente-ovnte, pinimtiliil. 



n. Berula. Fruit nearly globose, emarginnte at l)ase, with thickened epicnrp : oil-tubes numer- 

 ous and contiguous. Involucre and involucels present. Loallcts ovate-oblong to linear, 

 laciniately toothed. 



++ ++ ++ Fruit with prominent corky wings, didymous : stylopodium depressed : carpophore 

 2-parted. Stout perennials, with involucels and often involucres also. 



12. Cicuta. Fruit broadly ovate, with thick obtuse wings : oil-tubes .solitary. 



13. Sium. Fruit oblong or ovate : ribs wing-like : oil-tubes 2 or 3 in the intervals. 



♦ * Fruit somewhat conipressed laterally, linear-oblong, with broad commissure, not winged ; 



seed sulcate or rcnifbrm in section : carpophore 2-partcd, persistent : flowers white. 



14. Osmorrhiza. Fiuit narrowly attenuate at base, hisiiid on the acutish angles ; oil-tubes very 



obscure : seed sulcate on the face or somewhat involute. Umbels nearly naked. I>eaf- 

 lets ovate, cleft and toothed. 



15. Glycosma. Similar ; fruit not attenuate at ba.se, very rarely hispid : seed broadly sulcate. 



16. Podosciadium. Fruit not attenuate at base, glabrous : ribs filiform ; oil-tubes solitary or 



in j>airs : seed reniform in section and longitudinally ridged on the fftce. Involucre and 

 involucels present. Leaflets linear. 



♦ ♦ ♦ Fruit not compressed, or morn or loss compressed dorsally, obhmg to orbicular. 

 -H Fruit not compressed : flowers white. 



17. OEInanthe. Fruit oblong to glolwso : ribs corky and rcumded, with very narrow intervals 



and solitary oil-tubes. 



