422 DR. OTTO STAPF ON THE 
can scarcely be said that it is more differentiated or more advanced in development 
before it leaves the fruit than the embryos of a good many typical grasses; but it is 
much larger and possesses a more highly-developed vascular system. It differs further 
in its pronounced curvature, which results in the immediate juxtaposition of plumule 
and radicle, and in the similarity of the coleoptile and the leaves following it. The 
increased size of the embryo corresponds evidently to the increased bulk of the fruit, 
whilst both determine the copious supply with vascular strands. As to the curious 
curvature of the embryo, it appears to be connected with its downward movement in 
the growing fruit, from the point of origin in the interior to its final external 
position. By curving in this way it offers the minimum of surface to the tissue which 
is to be displaced, securing at the same time the simultaneous egression of radicle and 
plumule when germination sets in. The unusual structure of the coleoptile might 
similarly be explained by its peculiar function as the first of a succession of cataphylls 
which cover the axis of the seedling much as the sheaths, or “imperfect leaves,” of the 
stolon-shoots cover and protect their axes. 
Conditions as to which we have nothing to proffer but conjectures have so modified 
the evolution of Melocanna that its fruit has become viviparous. We know practically 
nothing about the ecology of the Melocanna forest; but so much is clear, that the 
immediate transition from maturation to germination and the particular fitness and 
readiness of the embryo plant to establish itself—conditions implied in vivipary—must 
give the seedlings of JZelocanna a certain superiority in the struggle with the numerous 
intruders which, in a tropical country full of conditions favourable for plant life, are sure 
to invade the ground as soon as the Melocanna jungle is fallow and dead. Vivipary 
in itself does not, of course, necessarily mean a large seed or fruit, but if we consider 
that the seedling of Melocanna attains a considerable size before it forms perfect leaves 
ready to assimilate, we shall understand why they are, in addition to their vivipary, so 
abundantly supplied with reserve food. All this necessarily means a large fruit, but also 
an increased surface for the scutellum, as the organ which induces the solution of the 
stored nutrient matter and its transmission to the growing parts; but increased surface is 
bound up with the development of a bulky body, of which only a limited portion can be 
utilized for the formation of vascular strands, the channels of building matter and water 
transport. The rest will be fundamental tissue, and it is only an instance of economy if 
we find in Melocanna this tissue acting as store-tissue in addition to the much ampler 
depot formed of the pericarp. The absence of a period of rest, and the consequent use- 
 lessness of a protective fruit- or seed-shell, made the pericarp available for the storage of 
the reserve materials coming from the mother-plant or in part formed almost in situ. 
The same reasons, if I may say so, allowed the plant to dispense with the testa ( generally 
prone to reduction in Graminez) ; and affecting still earlier phases in the ontogeny of the 
_ seed, they led to the suppression of the integument and the general reduction of the ovule. 
Hence the naked ovule and, at the other end of the line of development, the naked seed, 
it * seed" we may call it. Endosperm is still formed; but deprived of its normal function 
it collapses early, its empty crushed tissues acting as a “ diaphragm " between the peri- 
