SECRETARY'S REPORT. 75 



much as sedges and grasses are outwardly much alike — indeed some 

 species of the latter are called Carnation grass — but greatly dif- 

 ferent in quality ; grasses being for the most part nutritious plants, 

 whilst sedges are not only usually innutritious, but from the harsh- 

 ness of their herbage, are often a source of injury and annoyance to 

 the creatures that from starvation are sometimes doomed to eat of 

 them. 



The blade — lamina, is the expanded part of the leaf. It is some- 

 times large and drooping, as in the larger or flag-like grasses, but 

 occasionally it is very minute, especially when compared with the 

 sheath, as in the Avena pnhescens, (Soft Oat Grass.) In some spe- 

 cies the blade is long and the sheath short. The blade is traversed 

 by longitudinal pjarallel lines which are called the leaf veins or 

 nervures ; these may be hroad^ narrow^ rigid, soft, armed ivith 

 rongh hairs, and so on, all of which are not only points of distinc- 

 tion in species, but aid in making up the sum of those differences 

 which will ever be found in good and bad pasture grasses : as for 

 instance, grasses in which the herbage is covered with long downy 

 hairs, are mostly poor and innutritious in quality; on the other 

 hand, those of a harsh and rigid structure, with serrated leaves, 

 whose edges act as a saw, and whose flat blades perform the oflace of 

 a file, even if nutritious, would nevertheless be refused by cattle on 

 account of their mechanical inconvenience. 



The ligule, from the Latin ligida — spoon, scoop or strap. At 

 the point where the sheath ends and the blade begins, occurs a thin 

 and usually white semi-transparent membrane, termed the ligule or 

 tongue. This, as it varies so much in size and form, will be fre- 

 quently referred to in examining species, by some such terms as the 

 following : 



Short, in Poa pratensis — Smooth-stalked Meadow Grass ; 



Pointed, in Poa trivialis — Rough-stalked Meadow Grass ; 



Notched, in Bromiis mollis — Soft Brome Grass ; 



In pairs, in Ammophila arundinacea — Sea Sand Reed. 



Its value as a distinctive character may be drawn from an exam- 

 ination of Poa pratensis and P. trivialis, as it assists at a glance, 

 to distinguish two grasses much alike in appearance, though very 

 distinct in habit and general properties. The use which this part 

 of the leaf subserves would appear to be that of more securely fast- 



