IIORTUS GRAMINEUS WOBURNENSIS, 235 



ALOPECLFRUS geniculatus. Knee-jointed Foxtail-grass. 



Specific character : Culms ascending, bent at the joints; 

 panicle spike-like, cylindrical, obtuse; husks of the 

 calyx united at the base, obtuse, somewhat woolly; 

 apex of the corolla minutely notched. 



Obs. — There are two varieties of this species of fox-tail 

 grass; the present, which is by far the most common, 

 is distinguished from the other by its fibrous root and 

 greater size ; the less common variety has a bulbous 

 root. The alopecurus bnlbosus may be distinguished 

 from the bulbous-rooted variety of the knee-jointed 

 species by its upright culms, which want the knee- 

 jointed form so conspicuous in the culms of the former. 

 The anthers are at first of a purple colour, but after- 

 wards become ferruginous. 



Native of Britain. Root perennial. 



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

 a rich moist alluvial soil is 6,806 lbs. per acre. 



It grows common in surface-drains, and at the entrance 

 of cattle-ponds, particularly where the soil is clayey. It 

 docs not appear to be eaten with much relish by either cows, 

 horses, or sheep. Its nutritive powers are not considerable, 

 and its sub-aquatic natural place of growth excludes any 

 recommendation of it for cultivation. 



Flowers in the first week of June, and during the summer. 



GLYCERIA aquatica. Reedy Sweet-grass, or Poa aquatica. 

 Water Meadow-grass. 



Specijic character: Panicle erect, repeatedly branched, 

 spreading ; florets numerous, obtuse, v/ith seven ribs ; 

 nectary cloven, acute. Fig. 1. Spikelet of flowers 

 magnified. 2. The Germen. 



Ohs. — The creeping roots terminate in jointed culms; 

 fibrous roots numerous. Culms very high, from three 

 to six feet. Leaves straight, broad, smooth on every 

 part except the edges and keel ; sheaths a little com- 



