■.0 



r 



., ^f . 



268 



Elymus geniculatus. Knee-jointed Lyme-grass. 



r ■ 



Specific character: Spike bent perpendicularly downwards, loose; calyx, bristle-sha A 

 spreading, longer than the spikets ; leaves sharp-pointed. 



Obs. 



—The opposite specimen shews a singular habit of this grass ; the spike iust hef 



flowering, bends down by the assistance of a joint near the foot of the spike-stalk. En 1 



Bot. 1586. • S • 



Native of Britain. Root perennial. 



Experiments. — At the time of flowering, the produce from a sandy loam, is. 



Grass, 30 oz. The produce per acre 

 80 dr. of grass weigh, when dry 

 The produce of the space, ditto 



dr. qr. 



oz. 



326700 



lbs. 







32 



im S 



130680 



20418 12 

 8167 8 



The weight lost by the produce of one acre in drying 

 64 dr. of grass afford of nutritive matter 

 The produce of the space, ditto 



3 I 



24 04- 



16590 1 



12251 4 

 1036 14 1 



The root is powerfully creeping, and the foliage is tough and coarse. The quantity of nutri- 

 tive matter it affords is not considerable. It seems, therefore, to be but little adapted for usefid 

 purposes. Sir J. E. Smith, in the English Botany, informs us, that it was discovered in the salt 

 marshes at Gravesend by Mr. Dickson, and that Mr. Curtis was the first to distinguish it from 

 the Elymus arenarius, as it seems even Linnasus had confounded them. 



The Elymus arenarius is nearly allied to this species in its general habit, but differs specifi- 

 cally in the spikets being pubescent, more compact, and the spike perfectly upright. The leaves 

 are broader, culms taller and stronger, and the root is more ppwerfidly creeping. The pubes- 

 cence on the spikets, and the close order in which they are placed on the spike-stalk, with tJie 

 upright habit of the spike before and after flowering, seem to be good specific distinctions ; with 

 the exception of the last, as the two first indicate an excess of saccharine matter in proportion 

 to the other constituents of the plant, while the slender culms, distant florets, or loose spike desti- 

 tute of pubescence, with thin leaves, indicate the contrary. This is the case with the two 

 species now spoken of; the nutritive matter of the Elymus arenarius contains more than one- 

 third of its weight of saccharine matter, aijd that of the Elymus geniculatus contains but a very 

 small proportion. 



M 



•Huic affinis. 



dr. 



V 



Grass, 64 oz. The produce per acre 



80 dr. of grass weigh, when dry 



The produce of the space, ditto .- 



The weight lost by the produce of one acre in drying 



64 dr. of grass afford of nutritive matter 



The pr<?du.ce of the space, ditto r 



qr 



oz. 



697160 



lbs. 



= 43572 



45 

 576 



392040 



£4502 8 



5 



80 



54450 



19069 8 

 3403 2 



1 



4 



at in Germania hue usque baud observata, species est Elymus geniculatus. Smith, Britan. i. j 

 p. 153.— Cui culmi altiores, graciliores ; foha angustiora; spic^ sesquipedales, hipedales, , 

 lax* ; spiculae remotae ; glumae calicinaj lineari-setacccB flosculis longiores. 



At the time of flowering, the produce of the Ehmus arenarius on a clayey loam, is, 



