323 



(b) Bilobae (this and Bisectsc are Cotyledon terms 



E. acaciceformis. 

 E. acacioides. 

 E. aggregata. 

 E. angophot aides. 

 E. Behriana. 

 E. botryoides. 

 E. cinerea. 

 E. Clelandi. 

 E. cardata. 

 E. Dunnii. 

 E. elceaphora. 

 E. globulus. 

 E. goniocalyx. 

 E. grandifoUa. 

 E. Gunnii. 

 E. hemiphloia. 

 E. Kitsqni. 



(c) Bisectse : — 



E. leptophylla. 

 E. redunca. 



which will be explained later) 



E. leucaxylon. 



E. Maideni. 



E. Morrisi. 



E. Muelleri. 



E. oligantlia. 



E. Parramattensis. 



E. patens. 



E. populijolia. 



E. pulverulenta. 



E. punctata. 



E. rudis. 



E. sideroxylon. 



E. Stuartiana. 



E. unialata. 



E. urnigera. 



E. vemicosa. 



E. Woodwardii. 



E. uncinata. 



Lustre. 



Very few writers refer to the subject of the lustre of juvenile leaves. This is 

 readily understood, as very little has been written on juvenile leaves as such. Bentham 



says : — ■ 



. . . and the comparative colour of their surfaces, dark above and pale underneath or similar 

 on both sides, but this can rarely be ascertained from dried specimens. In general, it would appear that 

 the horizontal leaves have the two surfaces different, and the veins very divergent or transverse, and the 

 vertical leaves have the surfaces similar and the veins oblique ; so that where the leaves of the adult tree 

 are alternate lanceolate and foliate with oblique, veins, they are usually vertical, whilst the opposite ones of 

 the sapling of the same species are horizontal. (B.F1. iii, 187.) 



This deals with the difference in colour (see also a separate note on " Colour," 

 at p. 324), of the lower and upper pages or surfaces. I will presently give some species 

 in which it has actually been observed, and it will be noted that many are from regions 

 of comparatively high rainfall. We require further observations to ascertain our facts. 



It will be observed that Bentham employs the term " horizontal " for juvenile 

 leaves, and ''vertical" for mature ones. It will be seen from the drawings already 

 given in this work, that these terms are not quite satisfactory. They are technical 

 terms merely. We have other examples, in descriptive botany, of absence of strict 

 adherence to mathematical precision. Thus, in B.FI. i, vi (definitions), speaking of 

 venation, we have " When several (veins) start from the stalk, diverge slightly without 

 branching, and converge again towards the summit, they are said to be parallel, although 

 not mathematically so." 



