616 London Hotiicvltural Society ani Garden. 



tliose portions of the atmos[)heric air which are necessary for clahoratiuy 

 the sap, anil for exlialinj; the pises of which it rc(|uires to be deprivecl. 

 Parts of a i)lant are often called leaves, which arc, in fact, stems. The 

 professor exhibited a larjie branch of /discus androirynus (a kind of 

 butcher's broom), apparently covered with handsome dark green leaves, 

 on the surface of whicii were numerous flowers. These, the pro- 

 fessor stateil, were not really leaves, though nothing could, in shape, 

 texture, and colour, more strongly resemble what we are accustomed 

 to call by that name; but expanded branches, being all deficient in 

 that essential characteristic of true leaves, buds in the axils, and being, 

 of course, incapable of propagation. No portion of the branch of the 

 i^uscus, which he held in his hand, could, the professor observed, 

 be made to grow. Whether cut between the nodes, or being a part only 

 of the internodes, the effect would be exactly the same. The real leaves 

 of this plant are brown dry-looking scales, similar to those before de- 

 scribed as enclosing buds, and as being the abortive leaves of the |)reced- 

 ing year. To demonstrate this more clearly, Mr. Lindley exhibited a 

 stalk of i^uscus andr6gynus (strongly resembling a large head of asparagus), 

 the branches of which were not expanded, and on which the brown leaves 

 were distinctly visible : in the axils of these leaves buds form in the usual 

 way. Flowers, and real leaves, also form on the surface of the leaf-like 

 branches. 



These are not the only instances in which other parts of a plant may be 

 mistaken for leaves. Sometimes the petiole or footstalk of the leaf ex- 

 jiands till it becomes scarcely distinguishable from the leaf itself. This is 

 the case with the DionaeV/ Muscipula (or fly-trap), the leaves of which, 

 properly so called, are those parts armed with spines, which collapse, and 

 enclose flies, or other insects, that may hap[)en to touch them. The 

 fleshy parts, below these irritable leaves, are, in fact, only enlarged foot- 

 jstalks. The Sarraccnir/ (or side-saddle flower) is remarkable for the sin- 

 gular form of its leaf stalks, which are tubular, and hold water; while the 

 iW-penthes (or pitcher plant) has a very singular dilation of the petiole, 

 which forms a tendril, occasionally enlarging into the semblance of a leaf, 

 and ending in a complete pitcher, furnished with a lid, which is the leaf 

 itself. 



7''/o?<'e;-.? are only modifications of leaves; or rather, more correctly speaking, 

 they are, in fact, metamor|)hoscd branches ; there being no essential differ- 

 ence, in the eye of a botanist, between flower-buds and leaf-buds, and the 

 expansion of both being in effect the same. Every flower bud proceeds 

 from the axil of a leaf, culled a bractea, or floral leaf. On examining a 

 flower perfect iii all its parts (the professor exhibited a pa?ony), it will be 

 found that theso bracteaH divide the peduncle or footstalk of the flower, 

 liom the branch or stem ; and that they nometiuies form a single whorl, 

 joined together at their margins, and having the appearance c^f an outer 

 calyx. The flower, with its peduncle s[)ringing from these bracteas, is 

 exactly analogous to a branch sjjriiiging from the axil of a leaf; the pedun- 

 cle answering to the branch, and the calyx, corolla, stamens, and pistil 

 being metamorphosed leaves. The flower buds being thus in effect the 

 same as leaf buds, are, like them, produced at regular distances, and from 

 alternate sides of the stem. The transformation of leaves into petals is 

 clearly shown in the formation of the common tulif). This flower has no 

 calyx, or, at least, none that can be distinguished froni the corolla. It has 

 six leaves round its parts of fructification, which may be either called 

 petals or sepals ; or su|)posed to be three of each, birt there is no clear 

 mark of distinction, unless that of the three inner growing from a separate 

 whorl l)e deemeil a sufTuient one. The leaves on the stalk of the tulip, 

 or bracteas, arc often partially coloured like the corolla, as though they 



