HORTUS GRAMINEUS WOBURNENSIS. 349 



Produce per Acre, 

 dr. qr. Ibs. 



At the time the seed is ripe, the produce is 

 Grass, 20 oz. The produce per acre - - 13612 8 



80 dr. of grass weigh, when dry - 32 7 ^^ Q Q 



The produce of the space, ditto - 128 5 



The weight lost by the produce of one acre in drying 8167 8 

 64 dr. of grass afford of nutritive matter 237 ro^ 14 Q 

 The produce of the space, ditto - 13 3 5 



The weight of nutritive matter, in which the crop 

 at the time the seed is ripe exceeds that at the 

 time of flowering, is 146 3 



The proportional value of the grass of each crop is equal. 



This grass is properly a subaquatic. It will grow on tenacious 

 clays, but it seems only to thrive in very moist soils, or in such as 

 are for the most part covered with water. In moist woods it is 

 more frequent than any other of the creeping-stemmed bent 

 grasses ; here the culms often attain to five feet in height, when 

 supported by bushes. 



The above details shew the inferior nature of this grass, com- 

 pared to the larger, and even to the lesser-leaved varieties of 

 the Agrostis stolonifera. It cannot, therefore, as yet be con- 

 sidered in any other light than a weed that chokes up drains and 

 underwood. 



Flowers about the second week of July, and the seed is ripe 

 about the middle and towards the end of August. 



GLYCERIA. Generic character: Corolla awnless, cylindrical 

 furrowed, ribbed abrupt, not keeled ; seed loose, cylindrical 

 oblong. Sm. Engl. Fl. i. p. 40. 



Glyctria fluitans. Floating Sweet-grass. Sm. Engl. Fl. i. 

 p. 116. 



Poa fluitans. E. Bot. ; Flo. Ger. Flote Meadow-grass. Hort. 

 Gram. Fol. 239. 



Festuca fluitans. Host. ; Curtis ; Flo. Dan. Flote Fescue. 



German, Fluss-rispengras (mannagras). 



Specific character : Panicle oblong, branched, divaricating ; 

 spikelets close pressed ; florets numerous, obtuse, seven- 

 ribbed, with short intermediate ribs at the base ; nectary ob- 

 tuse, tumid. Sm. Engl. Fl. i. p. 116; Host. t. 77, F. fluitans; 

 E. Bot. 1520, Poa fluitans. , 



