DE. SPRUCE ON THE EECUNDATIOT^ OE GRASSES. 
9 
That grasses, notwithstanding their almost mathematical cha- 
racters, vary much as other plants do, is plain from the multi- 
tude of osculating forms (in such genera as E7'agrostis, Panicum, 
and Paspalum) which puzzle the botanist to decide when to com- 
bine, and when to separate, in order to obtain what are called 
"good species." Hence the conclusion is unavoidable, that in 
grasses, as in other plants, variations of surrounding conditions 
induce corresponding modifications of structure, and that amongst 
the former must be enumerated cross-marriages, however brought 
about. 
I have above sketched the inflorescence of a few diclinous 
grasses, some of them, such as Olyra, Fariana, and Gynerium, 
diff'ering so widely from one another that (excepting the cha- 
racters common to the order) the separation of the sexes is 
almost the sole feature that assimilates them. In all these, the 
self-fertilization of any one flower is out of the question. In the 
dioicous Gynerium, fertilization of the ovary by the male organs 
of the same plant is impossible ; in themonoicous genera it is not 
the only possible or even probable mode ; and in the synoicous 
genera it is not essential, seeing that the anthers very often do 
not burst until after the flower is opened, and that the stigmas 
are frequently so disposed as (apparently) to prefer fertilization 
by the pollen of other flowers. If the flowers of grasses be 
sometimes fertilized in the bud, it is probably exceptional, like 
the similar cases recorded of Orchids and many other families. 
I have myself not unfrequently seen in Melastomes a precocious 
crop of fruit produced from unopened flowers, with this curious pe- 
culiarity, that the fruit was small, dry, and few-seeded, instead of 
the normal succulent many-seeded berry ; but the seeds v/ere as 
perfect as those yielded by the fruit of fully developed flowers. 
To conclude : the more I ponder over existing evidence, the 
more I feel convinced that in its perfect state every being has 
the sexes practically separated, and that natural selection is ever 
tending to make this separation more complete and permanent ; 
so that the hypothesis of Plato, that the prototype even of man 
was hermaphrodite, may one day be proved to be a fact ! 
Richard Spruce. 
November 24, 1869. 
