THE GRASSES OF MAINE. 7 



staminate and pistillate flowers are on the same plant, it is said to 

 be monoecious, but when they are on separate plants they are said to 

 be dioecious. 



The pistil consists of three parts, an ovary, a style and a stigma. 

 The ovary contains the ovule or the rudimentary seed, and from the 

 top of the ovary two styles extend upwards with feathery stigmas 

 at their tops. The flowers are usually furnished with two or three 

 minute scales (squamulce) near the base of the pistil. The sta- 

 mens consist of a long, slim, thread-like body called the filament, 

 which arises near the base of the ovary, and to its outer end is 

 attached the anther, a sort of case deeply notched at each end, and 

 within which is a cavity on each side, in which the pollen, or fertiliz- 

 ing powder, is developed. There are usually three stamens in each 

 flower, though sometimes only one or two. When the pollen is 

 mature, the sides of the anther split open lengthwise, and the pollen 

 is scattered by the wind, and falling on the feathery stigma of the 

 pistil, fertilizes the ovule within, so that it developes into a seed 

 capable, under favoring circumstances, of producing another and, 

 similar plant. These pollen grains are composed of an outer, some- 

 what hard and roughened covering, within which is a separate but 

 delicate sack-like lining filled with a dense fluid often containing a 

 large number of minute granules. When a grain of pollen falls on 

 the stigma, it absorbs moisture, bursts the outer covering, and the 

 inner sack extends down through the tissues of the style in the form 

 of a long fine tube, still holding the granular contents of the original 

 pollen grain. This tube penetrates the ovary, and coming in con- 

 tact with the ovule, fertilizes it, probably by the contents of the tube 

 passing through and mingling with those of the ovule. 



The protecting organs are somewhat chaffy and scale-like in 

 appearance, and consist of an outer pair, one on each side, called 

 glumes, outer glumes or lower glumes, within which are one or more 

 flowers, each of which is enclosed within another pair of protecting 

 organs, the lower or outer one of which is called the flowering 

 glume, and the one on the opposite side, the edges of which are 

 often enclosed by the flowering glume, is called the palea or palet. 

 See plate XXXV, a, which represents the pair of glumes widely 

 separated at the top, and the flower represented as separated and 

 raised above the glumes, showing the large flowering glume on the 

 right, the smaller palea on the left, and three stamens, two on the 

 right within the flowering glume, and one on the left above the 



