52 TRIANDRIA. MONOGTNIA. 



(or united near the base). In most of the species the 

 awn is geniciilated or bt^iu at an obtuse angle. 



Species. \. pratensis. (Naturalized; frequently assuming 

 the decumbent habit of A. genicxdatus. According- to Des- 

 fontaines this species is subject to the parasitic affection of 

 microscopic Jungi^ called in France Ergot^ 2. subarista- 

 ius-\ Mich. 



Nearly all the g-enuine species of this genus are con- 

 fined to Kurope, also extending into Barbary in Afri- 

 ca. There are 10 species described, of which there are 2 

 at the Cape of Good Hope, and 1 at the straights of Ma- 

 gellan. 



79. PANICUM. L. (Panick-grass.) 



Calix S valved, exterior valve often rery 

 small, 1 -flowered, (mostly with the rudiments 

 of a se.ssile, neutral or masculine floret.) Ctwol- 

 la (hermaphrodite) 2-valved, cartilaginous and 

 persistent. 



Flowers densely or loosely paniculate, the panicle some- 

 times recemosely divided, with lateral conglomerations up- 

 on an angular racliis; but for the most part diffuse or spread- 

 ing, pyramidal, divaricate, or dicliuLomous, every where 

 terminated by single flowers, approximating by pairs. In 

 many species, the accessory, now considered the outer 

 glume of the proper calix, is very minute, in these spe- 

 cies the calix is often oval, or obovate, pubescent, with 

 the imperfect flower always destitute of sexual rudi- 

 ments, and the panicle divaricate. Some other species 



•j- Culm about a foot high, and as well as the sheathes 

 glaucoits, repent at tlie base, or geniculate. Leaves smooth, 2 

 or 3 inches long on the culm; stipula elongated, semicylindric. 

 Spike 1 to 2 inches long, somewhat attenuated above, cy- 

 lindric, a little lobed or divided near the base. Flowers ovate 

 obtuse, a little dilated. Calix connate at the base, conspicu* 

 ously ciliate on the carina and margins. Corolla obtuse, 

 smooth, edged with green as well as the calix; awn a little 

 exserted, straiglit, originating somewhat below the middle of 

 the valve. Stigmata white, filiform, exserted more than the 

 length of the corolla, scarcely plumose. 



In the waters and on the margins of ponds, in Upper Canada. 

 ^\fr. Whitlow. In New-Jersey, near Philadelphia. Nearly allied 

 to A. geniculatus, but the flower is not awned from the base, 

 and the awn is also straight. 



