HORTUS GRAMINEUS WOBURNENSIS. 275 



valves acuminate ; blossom one valve, awned ; awn fixed a 

 little above the base. 

 Obs. — This species of bent is distinguished from the Agrostis 

 vulgaris mutica, and Agrostis vulgaris canina, to which in habit 

 it approaches, by the corolla or blossom being but of one valve ; 

 from the Agrostis nivea, vel Trichodium niveum, by the erect 

 disposition of the stem, and the awn which is fixed but a little 

 above the base of the valve : the valve has likewise two short 

 awn-like points, which are a continuation of the nerves of the 

 valve. The panicle is also less divided, more spear-shaped, 

 and the calyx is acuminated. Whole plant of a fine deep 

 green colour, by which it is distinguished at first sight from 

 every other species of bent-grass. The culm of this species 

 oi Agrostis is perfectly upright from the root, and not in the 

 least decumbent or ascending in any part. 



German, Felsen-Straussgras. 



Native of Britain ? Root fibrous, perennial. 



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



bog soil is — 



Produce per Acre, 

 dr. qr. lbs. 



Grass, 14 oz. The produce per acre - 9528 12 



80 dr. of grass weigh, when dry - 40 7 a-jc^a f: (\ 

 The produce of the space, ditto - 112 3 

 The weight lost by the produce of one acre in drying 4764 6 

 64 dr. of grass afford of nutritive matter 1 2-iV ^ 9,-1 q ir: 

 The produce of the space, ditto - 5 1| 3 



At the time the seed is ripe, the produce is — 

 Grass, 11 oz. The produce per acre - 7486 14 



80 dr. of grass weigh, when dry - 29 7 971'^ K 14 

 The produce of the space, ditto - 63 83^ i "^ 

 The weight lost by the produce of one acre in drying 4772 14 2 

 64 dr. of grass afford of nutritive matter 12 ^ ,„^ „ q 

 The produce of the space, ditto - 4 0/^3 



The produce of latter-math is — 

 Grass, 4 oz. The produce per acre - - 2722 8 



64 dr. of grass afford of nutritive matter 12 - 63 12 15 

 The weight of nutritive matter which is lost by 



leaving the crop till the seed be ripe, is - 75 8 6 



As it will be found a vain attempt to cultivate or maintain 

 grasses on soils of a nature opposite to those which naturally 



