PROFESSOR BALFOUR ON THE IPECACUAN PLANT. 787 



Figure 2. Elliptical leaf, about the average natural size, having a blunt apex, with midrib and curved 

 veins indicated by dotted lines. 



Figure 3. An annulated root, slightly enlarged. This is the pharmaceutical part of the plant. The 

 cortical portion (a, a) composed of cells containing starch grains ; this portion is in the form 

 of rings closely applied to each other. The meditullium (b) is the central woody portion. 

 Processes are seen projecting from this, which are concerned in the formation of leaf-buds. 



Figure 4. Capitulum, or head of gamopetalous funnel-shaped sessile flowers, white and sweet-scented, 

 having each a five-divided limb, and being all surrounded by a four-leaved involucre. The 

 capitulum is magnified rather more than twice the natural size. 



Figure 5. Flower from the old Hookerian specimen of the plant, magnified. The corolla is split down 

 to the base, to show the organs of reproduction. The corolla is funnel-shaped, and has a five- 

 divided limb, with broadly ovate and pointed segments. The ovary (c) is inferior, and is 

 crowned by the irregularly toothed limb of the calyx. The stamens (a) are five in number, 

 and in this case are longer than the style (6), which terminates in a two-lobed stigma. 



Figures 6 and 7 show the dimorphic flowers of the plant. (Magnified.) The two forms are required 

 for complete fertilisation. 



Figure 6. Flower taken from one of Dr Gunning's plants, showing ovary (c) crowned by calyx; 

 tubular corolla, with one of the segments cut off to show the long stamens (a) ; and the short 

 style (b) with stigma. 



Figure 7. Another flower taken from one of Dr Gunning's plants, with a portion of the corolla 

 removed to show the short stamens (a) and the long style (b) ; the ovary (c) is inferior. 



Plate XXXII. 



Figure 1. Portion of Ipecacuan plant (Cephaelis Ipecacuanha), showing a somewhat shrubby stem (a), 



wavy leaves (b, b), and drupaceous fruit (c), supported on a peduncle, which is bent down- 

 wards. This is a young plant about the natural size. 

 Figures 2 and 3 show microscopical sections of the young stem, about one year old. The dissection 



made by Mr John Sadler, my assistant. 

 Figure 2. Transverse section of young herbaceous stem, the epidermis (a, a) shows delicate cellular 



hairs, the cortical portion (b, b) composed of angular cells, vascular bundles in wedges (c, c), 



cellular pith (d). Magnified about thirty diameters. 

 Figure 3. Longitudinal section of the same stem more highly magnified. This section does not extend 



to the epidermis. Cortical cells (b, b) ; vascular bundles (c, c), consisting of spiral, pitted, 



and woody tubes ; hexagonal pith (d). 

 Figures 4 and 5. Sections of the root, also made by Mr Sadler. 

 Figure 4. Transverse section of the root (magnified), showing outer epidermal portion (a, a) ; the 



cortical portion (b, b), composed of cells containing many starch granules ; central portion, 



meditullium (c), composed of wood tubes. 

 Figure 5. Longitudinal section of the root (magnified), showing epidermal portion (a, a), containing 



starchy cells (b, b) ; central woody and pitted vessels (c). 

 Figure 6. Two portions of the annulated root bearing leaf-buds, showing the mode in which the plant 



may be propagated. The root having both the functions of an ordinary root and a stem. A 



very small portion of a root, not larger than the §• of an inch, will do for the purpose of 



propagation. 

 Figure 7. Young Rio Janeiro plant, from Dr Gunning's specimens, showing somewhat quadrangular 



herbaceous stem, opposite, ovate, acute, delicate leaves. 

 Figure 8. United stipules which embrace the stem ; each is divided at the apex into four long narrow 



segments. Magnified about six times. 

 Figure 9. Glands at the base of the stipules, of a somewhat ovate-lanceolate shape, composed of cells. 



Highly magnified. 



