374 COMPOSIT.E. IvA. 



18. IVA. Linn. ; DC. prodr. 5. p. 529 ; Endl. gen. 2485. MARSH ELDER. 



[Origin of the name uncertain.] 



Heads monoecious, not radiate. Fertile flowers 1-5, marginal, with a small tubular corolla : 

 sterile flowers usually 7-20 (rarely fewer) ; the corolla somewhat campanulate or funnel- 

 form, 5-toothed. Scales of the involucre 3 - 5, in a single series and often somewhat united, 

 or 6 — 9 and imbricated. Receptacle small, chafiy. Anthers nearly or quite distinct. 

 Style in the fertile flowers deeply 2-cleft, the branches linear ; in the sterile undivided, 

 usually radiate-pencillate at the apex, Achenia obovoid, somewhat compressed, without a 

 pappus. — Herbaceous or shrubby plants, mostly growing near the salt water or in saline 

 soils. Leaves opposite or the upper ones alternate, often thick or fleshy. Heads nearly 

 sessile, deflexed, solitary or ternate in the axils of the upper leaves or foliaceous bracts, 

 forming leafy spikes or racemes. Corolla greenish-white. Anthers yellow. 



1. IvA FRUTESCENS, Linti. Highwater-shruh. 



Sufirutescent, much branched, nearly smooth ; leaves oval and oval-lanceolate, the lower 

 ones opposite, the uppermost alternate, rather fleshy, coarsely serrate ; heads depressed- 

 globose, on short pedicels, solitary or in pairs in the axils of the bracteal leaves ; scales of the 

 involucre 5 ; chaff of the receptacle linear-filiform. — Linn. sp. 2. p. 989 ; Lam. ill. t. 166. 

 /. 2 ; Michx. fl. 2. p. 184 ; Willd. sp. 3. p. 2386 ; Pursh, fl. 2. p. 580 ; Ell. sk. 2. p. 475 ; 

 Bigel. fl. Bost. p. 317 ; Beck, hot. p. 209 ; DC. prodr. 5. p. 529 ; Terr. ^ Gr.fl. N. Am. 

 2. p. 287. 



Stem 3-5 feet high, the branches annually dying down nearly to the ground, except in 

 mild winters. Leaves thick and somewhat fleshy, 2-3 inches long and 1-2 inches wide, 

 dull green, 3-nerved, with a minute appressed pubescence on both sides, and a little roughened 

 with elevated dots ; the teeth rather acute. Heads numerous, about two lines in diameter, 

 greenish. Corolla of the fertile flowers minute ; of the sterile flowers funnel-form. Achenia 

 sprinkled with resinous dots. 



Seacoast of Long Island, and borders of salt-marshes on the Island of New- York. August 

 - September. 



