226 HORTUS GUAMINEUS WOBURNENSIS. 



grey colour ; it is essentially distinguished from the others by the 

 laro-er valve of the blossom being furnislied with a minute awn, 

 which rises a little above its middle, and reaches to the top of the 

 valve ; the awn is straight, and pressed close to the back of the 

 valve. 



The above characters of distinction, and the figures which 

 are afterwards given to illustrate them, were taken from plants 

 raised from seed on the same soils that the plants were found na- 

 turally growing on, and on different soils ; the characters of the 

 wild plants were compared with those of the cultivated ones, and 

 what remained constant after these changes of circumstances are 

 the above. It is easy to conceive the change that takes place in 

 the general appearance of a plant when brought out of a wet ditch 

 and cultivated on a dry exposed soil, or from under the shade of 

 trees on a poor sand, and planted out on a rich loam with full ex- 

 posure to the sun and air. Characters, therefore, that change 

 with these changes of circumstances, tend more to perplex than 

 enlighten, and may therefore be better omitted. 



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

 active peat soil is — 



Produce per Acre, 

 dr. qr. lbs. 



Grass, 26 oz. The produce per acre - 17696 4 



80 dr. of grass weigh, when dry - 35 J ^^^2 i i o 

 The produce of the space, ditto - 182 ) 



The weight lost by the produce of one acre in drying 9954 2 4 

 64 dr. of grass afford of nutritive matter 3 2) g^y 19 o 

 The produce of the space, ditto - 22 3 5 

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

 Grass, 28 oz. The produce per acre - 19057 8 



80 dr. of grass weigh, when dry - 36 9 gr^^ j^ q 

 The produce of the space, ditto - 201 2f ) 



The weight lost by the produce of one acre in drying 10481 10 

 64 dr. of grass afford of nutritive matter 3 2) }oao q c 

 The produce of the space, ditto - 24 2 ) 



The weight of nutritive matter which is lost by 

 taking the crop at the time of flowering, exceeds 

 one-fourteenth part of its value, and is - 74 7 2 



The produce of latter-math is — 

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



64 dr. of grass afford of nutritive matter 50 gr. 70 14 6 



