120 BOARD OF AGRICULTURE. 



There the pistillate flowers are at the top of the stalk, and 

 the staminate flowers below ; so that the pollen, contrary to 

 the other example, must rise to fertilize the germ. 



Then there is another class of grasses, which may be called 

 polyf/amous grasses^ where a portion of the flowers will be 

 wholly staminate, another portion wholly pistillate, and an- 

 other and larger portion perfect, including both sexes. A 

 few of the grasses belong to this class; for instance, some 

 species of the panic-grasses, and a few of the wood-grasses, 

 called andro'pogon by the botanists. 



But by far the greater number, almost the whole, of our 

 natural and cultivated grasses and grains, have perfect flow- 

 ers ; that is, the staminate and pistillate flowers are arranged 

 together, and fertili'zation takes place in many cases before 

 the flower opens. Those are what are called perfect flowers, 

 where the pistils and stamens are arranged together in the 

 same covering, and where the two parts come to maturity at 

 the same time. Of course cross-fertilization, or fertilization 

 from other species, could not take place in such plants ; and 

 hybridization does not take place, as it does when different 

 varieties of Indian corn grow near each other. 



Now, with regard to these perfect-flowered plants, which 

 constitute by far the larger portion of our natural grasses, 

 there are some peculiar circumstances which might make 

 cross-fertilization possible. In a few of them the stigmas 

 are thrust out of the covering before the stamens ; and they 

 will retain their fertilizing power, their freshness, but a very 

 short time. They must get their pollen from flowers already 

 opened. Take, for instance, our common sweet-scented ver- 

 nal-grass. There the stigmas are thrust out before the sta- 

 mens appear, and they must be fertilized by flowers which 

 have previously opened before the pollen appears in its own 

 flowers. I think there are one or two other species of grasses 

 of that kind, as the meadow-foxtail. The reed canary-grass 

 is another example where the stigma is thrust out before the 

 stamen appears ; but, in that case, the stigma retains its fresh- 

 ness longer than in the case of the sweet-scented vernal-grass. 

 Possibly cross-fertilization might take place in such a plant 

 as that ; but practically I should say that cross-fertilization 

 would not be possible in most of our natural grasses, though 

 it is very common in Indian corn. 



