BY CUTHBERT HALL. 517 



Eastern Australia. It does not seem to occur in the North and 

 North-Eastern coastal areas of the continent, nor is it found on the 

 high mountain-ranges nor in Tasmania. It is a dry-country type, 

 and many of these species are Mallees ; in fact, all the Mallees 

 have either this kind of cotyledon, or the small, oblong, round 

 or reniform cotyledon. The origin of the peculiar rootstock of 

 the Mallee can be well seen by observing the seedling. In nearly 

 all the Eucalyptus seedlings, and also in the Angophoras, there is 

 developed, especially if growth is checked, a small woody swelling 

 in the stem at the point of attachment of the cotyledons. A 

 number of buds will develop on this, and shoots start from them. 

 If the growth of the seedling proceeds in the form of one main 

 stem, this swelling is soon obliterated, but, in the Mallee, these 

 secondary shoots grow almost as quickly as the main stem, and 

 so, instead of a tree in the ordinary sense, we have an enlarged 

 rootstock, from which spring numerous stems, all more or less of 

 the same size. As far as known, the oils of this group contain 

 eucalyptol and pinene, and many of them aroraadendral; phellan 

 drene is quite absent. Almost all belong to the Parallelantherse, 

 E. uncinata, of the Porantherae, being an exception. Generally 

 the anthers of these species are small. 



Foldirig of the Cotyledons in the Embryo. 

 The shape and size of the seed are largely determined, when 

 endosperm is absent, by the size, shape, and manner of folding 

 of the cotyledons. Moreover, the size and shape of the fruits 

 must be largely determined by the shape, size, and number of 

 fertile and sterile seeds they contain. In Angophora, the fruits 

 are large to accommodate the single, large, flat, fertile seed in 

 each cell ^o, too, with the " Bloodwoods," where there is one 

 fertile seed in each cell, and a few sterile ones. The occurrence 

 of the single fertile seed permits of the development of the winged 

 appendage of the testa, many of the members of this group 

 possess, and which is impossible in the smaller fruits, with closely 

 packed seeds, of the majority of the Eucalypts. 



Three main types of folding may be distinguished : 

 (i.) That found in E. corymbosa, and those species with similar, 

 entire, reniform cotyledons. Here the fold in each cotyledon 



