376 CLXXIII. GBAMINE^. (Bambusew, Gamble.) [Arunrlivaria.. 



first time the true characters of the two types of sheath and blade that occur in 

 Bambusece, and which do not obtain, so i'ar as I know, in any other tribe of grasses. 

 In a communication which Mr. Mitford has been good enough to make to me on this 

 subject, he has formulated his views as follows, and has kindly allowed me to 

 introduce them here. 



" The sheath is an organ playing so important a part in the life of the Bamboo 

 that it deserves something more than a cursory notice. In the grasses generally the 

 sheath is regarded by botanists as taking the place of the petiole of the leaf! It 

 happens, however, that the leaves of most Bamboos indued of all the hardy Bamboos 

 have a distinct continuation of the midrib of the leaf attaching it to 'the sheath 

 and articulated, which continuation might perhaps be correctly termed a petiolule. 

 The Bamboos, as it appears, bear sheaths of two types. There is first of all the 

 series of sheaths which, borne one on each node and wrapped tightly round the 

 culm or branch, as the case may be, protect it during growth. This form of sheath 

 is divided or split transversely into two members, the ligule and the 15 m bus or blade, 

 the latter being what, I would term a psendophyll, or false leaf, sessile, lacking both 

 midrib and petiole, varying in size in the different species, but always the n'rst part 

 to wither and disappear. In some Bamboos those of the Phyllosiackys group 

 this sheath falls away as soon as branching takes place; in others, of the Arun linaria 

 group, it remains, and having guarded the tender growth of the parent culm or 

 branch it springs aside with the young branches or brauchlets, devoting the remainder 

 of its life to their protection until they can stand alone. 



" Then there is the second form of sheath bearing a true leaf with petiole and 

 midrib. This is the form assumed by the two, three, or four sheaths at the top of 

 each culm branch and branch let above the topmost node where branching ends. 

 This true leaf is persistent upon the sheath. r lhe ligule is present, as in the first 

 type, but the deciduous pseudophyll is replaced by an evergreen leaf. 



" An interesting question arises as to whether there is any transition stage 

 between the two types of blade, or whether the change is always sudden. I think 

 that in many Bamboos I can trace such a transition stage; that is to say, that each 

 successive psendophyll ou the stem becomes more and more like a true leaf, something 

 of the nature of an arrested midrib being perceptible in the pseudophylls which are 

 found near the top of the culm, though it is not until the last branching node Iras 

 been passed that the true leaf .bearing sheaths occur. The principle remains in- 

 violate (throughout the hardy species at any rate), and the distinction between the 

 two classes of sheaths is absolutely maintained." A. B. F. M. 



I would remark in conclusion that Mr. Mitford's observations, extending to the 

 nervation of the leaves of Bamboos, lead him to the conclusion that of those cultivated 

 by him in the open air in the middle of England, the truly hardy only have tessellated 

 leaves ; the tender, such as Arundinaria .Faiconeri and falcata, having very incon- 

 spicuous transverse nervules, or none. J. 1). H. 



Subtribe I. ARUNDINABIE.E. (See p. 91.) 

 132. ARUNDXNARXA, MicJix. 



Erect or climbing shrabs. Stems slender, nodes usually prominent, 

 iuternodes rather short, branches short fascicled. Stem-sheaths papery, 

 straw-colrd., blade subulate. Leaves usually small, jointed on tue sheata. 

 Infl. on separate stems, or terminal, or on leating branches. S pikelet* 

 1- many-fld., compressed, usually all bisexual, except sometimes the 

 terminal, often sheathed; empty gls. 2, unequal, membranous; rig. gls. 

 longer, obtuse acute or mucronate, many -nerved. ; palea 2-keeled. Lodicules 

 3, ciliate. Stamens 3, rarely up to 6. Ovary globose above ; style suort, 

 stigmas 2-3 plumose. Grain ovoid or narrowly oblong, dorsally furrowed, 

 included in the gl. and palea. Species about 50, 14 American, 1 African, 

 the rest Asiatic. 



