THE SEEDS OF THE GRASSES. 155 



the apex, and juts out like a bone. The seeds of F. elatior are 

 grey, long, and rather narrow. Those of F. pratensis are faded 

 straw colour, smaller, and more elastic. The seeds of the other 

 fescues are much smaller, those of F. ovina being only half as 

 long ; but to distinguish between them, as known to commerce, 

 is futile, if, according to Percival, they are all derived from 

 the same parcel — as they certainly seem to be — by screening, 

 the smallest without awns being sent out as F. ovina (tenui- 

 folia), the larger with tapering awns going as F. duriuscula, 

 and so on. As a rule those of F. ovina are yellowish brown, 

 those of F. rubra are greyish brown and stouter in form, with 

 the awn rising sharply, those of F. duriuscula are grey and 

 hard looking, and those of F. heterophylla greyer and flatter and 

 having a stouter awn. 



In the poas the seed is small — about the same size as that of 

 F. ovina — and angular in appearance, and the grain is loose within 

 the paleae and shakes out readily. In Poa pratensis the palea is 

 nerved, long, and brownish ; the grain is ovate, pointed at both 

 ends, the apex bearing remains of the stigma ; it is rounded on the 

 back and concave on the other side, and has no groove, or only 

 a faint indication of one. In P. trivialis the palea is smooth 

 with distinct ribs, long, brownish, the grain being ovate, rounded 

 at both ends, and having a well marked groove on the ventral 

 surface. Of the two other species used in farming, P. compressa 

 has a nearly glabrous seed with obtuse paleae, and P. nemoralis 

 has a short, pointed seed without nerves or hairs. 



Very different seeds are those of the yellow oat, A vena /7a- 

 vesceus, which are so enveloped in the chaffy paleae — the long, 

 kneed, twisted awn being conspicuous — that they look and feel 

 like particles of fluff, the stalk being flat and hairy and the 

 grain flat, slender, pointed at both ends, and having no groove 

 on its yellow, shining surface. Another soft seed is that of 

 Yorkshire fog (Holcus lanatus), which consists of the whole 

 spikelet, the paleae enclosing the grain, those of the barren floret, 

 and the glumes, all silvery white, and easily known by the awn, 

 which began straight and curved into a hook as the fruit ripened 

 into the grain, which is ovate, pointed, and hairy at the tip and 



