THE PEDIGREE OF WHEAT. 



675 



Finally, we come to the most important part of all, the ovary. 

 This part, alternating with the stamens, has the same arrangement of 

 styles relatively to the axis as in the case of the petals ; and it has 

 undergone precisely the same sort of abortive distortion. The two 

 outer styles, hanging freely out of the calyx, have been preserved like 

 the two outer lodicules ; but the inner one, pressed between the grain 

 and the inner pale (with the stem behind it), has been simply crushed 

 out of existence, like its neighbor the inner lodicule. 



Thus the final result is that the whole inner portion of the flower 

 (except as regai'ds stamens) has been distorted or rendered abortive 

 by close pressure against the stem (due to the crowding of the florets 

 in the spiky form), while the whole outer portion remains normal and 

 fully developed. We have an outer pale representing a single normal 

 sepal, and an inner pale representing two dwarfed and united sepals ; 

 we have two normal outer lodicules or petals, and a blank where the 

 inner petal ought to be ; we have three stamens, symmetrically ar- 

 ranged, among the faithless faithful only found ; and we have finally 

 two normal outer styles, with a blank in place of the absent inner style. 

 The accompanying diagram, com- 

 pared with that already given, will 

 make this perfectly clear. 



Here, a 1 represents the outer pale 

 or normal sepal, while 2 and a 2 rep- 

 resent the inner pale composed of the 

 two united sepals. Again, b l and b* 

 stand for the two lodicules or surviv- 

 ing petals, while b z marks the place 

 of the lost petal, now found in the 

 bamboos alone. The stamens are let- 

 tered c 1 , c", and c 3 . The two existing 

 styles are shown by d l and d-, while 

 d 3 marks the abortive inner style, 

 now not even present in a rudimentary condition. It will be observed 

 at once that all the outer side is normal, and all the inner side more or 

 less abortive through pressure against the axis. 



Thus it will be seen that the line of links which connects the grasses 

 and cereals with the lilies is absolutely unbroken, and that it consists 

 throughout of one continuous course of degradation. At the same 

 time, by this one-sided and spiky arrangement, the grasses secured for 

 themselves an exceptional advantage in the struggle for existence. 

 Xo other race of small, wind-fertilized plants could compete with them 

 for the possession of the open, wind-swept plains ; and over all these 

 they spread far and wide, rapidly differentiating themselves into a vast 

 number of divergent genera and species, each aclaptively specialized 

 for some peculiar habitat, soil, or climate. At the present time, the 

 gi-asses number their kinds by thousands ; they extend over the whole 



