k 



AMAUANTACE.E. (aMAHANTII IAMII.Y.) 429 



2. ACNIDA, Mitch. Watku-Hkmi-. 



Characters of Ainarantus, except tliat the flowj-rs are ronipletolv dioecious 

 aud the pistillate ones witliout calyx. Bracts I -3, uueipial. Staininate calvx 

 of 5 thin oblong imicrouate-tipped sepals, longer than the hracts ; stamens 5, 

 the anther-cells united only at the middle. Stigmas 2-5, often long and plu- 

 mose-liispid. Fruit somewhat coriaceous and indehiscent, or a thin membran- 

 ous utricle dehiscing irregularly (rarely circumscissile), usually .3-5-angled. 

 (Name from a- privative, and kvISv, a nettle.) 



§ I. ACNIDA proper. Fruit indehiscent, with jinn aud i-iosf jiirirarp. 



1. A. cann&bina, L. Usually stout, 2-G° high or more, glabrous; 

 leaves lanceolate to linear-lanceolate, acuminate, long-j)eti()le(l ; sepals of sterile 

 flowers ovate-oblong, obtuse or acutisli ; bracts usually thin and lax, much 

 sliorter than the fruit, sometimes more rigid and longer; fruit ab<nit 1" long, 

 obovate, the pericarp rather thin, more or less rugosely angled ; seed somew hat 

 turgid, not angled, usually less than 1" loug, shining. — 4Salt or brackish 

 marshes, coast of N. Kng. to Fla. 



2. A. rusocarpa, Mlchx. Very similar; fruit larger, 1^-2" long, the 

 pericarp thicker, and tlie larger seed flattened with thick margins, usually 

 thickest on the cotyledonar side. — N. Y. (^) and Teun. to S. Car. ; apparently 

 much less common than the last, though it is often difficult to positively dis- 

 tinguish the species from the immature fruit. 



§ 2. MONTELIA. Fruit dehiscimj irregular/ 1/, the pericarp thin, loose and usu- 

 al/ 1/ roughened ; not salt-marsh plants. 



3. A. tuberculata, ^Nloq. Tall aud erect, or sometimes low and decum- 

 bent; leaves lanceolate, acute or acutish or sometimes oljtuse ; sepals of sterile 

 flowers lanceolate, acute or acuminate; pistillate flowers closely clustered in 

 more or less dense naked or leafy axillary aud terminal spikes (ar the axillarv 

 cajjitate) ; bracts rather rigitl, acuminate, equalling or exceeding the fruit: 

 utricle about ^" long; seed shining, -J- J" in diameter. (Montelia tamaris- 

 ciua, (Jrai/, in part.) — Ohio to Dak., Mo., Ala., and La. 



Var. SUbnuda, Watson. Erect or often prostrate, the lower clusters at 

 least of pistillate flowers more or less cymose aud often in globose heads ; bracts 

 thinner, narrow and lax, shorter than the fruit. (M. tamariscina, var. coucate- 

 nata, O'rai/, in part.) — W. Vt. (Oahe.s) ; Out. to Minn., and .southward. Often 

 appearing quite distinct from the type, but intermediate forms are not rare. 



3. I RE SINE, IMJrowno. 



Flowers mostly polygamous or dioecious, 3-bracteil. Calyx of 5 sepals. Sta- 

 mens mostly 5; filaments slender, united into a short cup at base; anthers 

 1-celled, ovate. Fruit a globular utricle, not opening. — Herbs, with opposite 

 petioled leaves, and minute scarious-white flowers, crowded into clusters or 

 spiked aud brandling panicles ; the calyx, etc., often bearing long wool (whence 

 the name, from flpfaiwyr], a wreath or staff entwined with fillets of wool). 



1. I. celosioides, L. Nearly glabrous, annual, erect, slender (2-4° 

 high); leaves ovate-lanceolate ; panicles very slender, often l)road and difTuse, 

 naked; bracts and calyx silvery -white, tiie fertile calyx twice louger than tlie 



