THE SEEDS OF THE GRASSES. 159 



PsAMMA. — The seed of marram is three-eighths of an inch in 

 length, linear-lanceolate in shape, and ivory white in colour, 

 with a tuft of hairs at the base ; the grain is brown and grooved. 



Sesleria, — The palea of 5. carulea is mucronate and serrulate, 

 and the seed is oblong and greyish yellow. 



Triodia. — In T. decumbens the central tooth of the palea is 

 characteristic, and a further distinction is the hairy base. 



An attempt at a tabular scheme by which all our hundred and 

 one species can be recognised by their seeds is, let us say, a task 

 not to be lightly undertaken ; but the following key to the 

 identification of those of the chief pasture grasses — and their 

 most frequent associates — deals with the varieties for quickly 

 distinguishing which some short method is likely to be 

 useful. 



Seed awnless. 



Grain without a groove. 



Grain free or with palea only, small and ovoid- acute. 



Phleum pralensc. 



Grain not free. 



Hilum linear and long. 



Grain broader at apex than at base. Fesluca ovina. 

 Grain not broader at apex than at base. Digraphis 

 arundinacea. 

 Hilum linear and -short. Dactylis glomevata. 

 Hilum round, seed angular. 

 Palea pointed. Poa pralensis. 

 Palea blunt. Poa nemoralis. 



Grain with a groove. 



Grain broader at apex than at base. 

 Hilum linear and long. 



Colour grey. Fesiuca elalior. 



Colour whitish yellow. Festuca pralensis. 



Grain not broader at apex than at base. 

 Seeds rounded. 



Rachilla obsolete ; seed small. Agrostis slolonifera. 

 Rachilla short, flat, angular. Lolium perenne. 

 Rachilla short, smooth, dilated above. Cynosurus 



crislatus. 

 Rachilla stout and hairy. Elymus arenarius, 



