J. M. Macfarlane. — Cephalotaceae. 7 



superior, but with their xylems inclined toward each other, and iheir extra-phloem 

 sclerenchyma patches directed outwardly. Over the lower epidermis stomata and glands 

 are alike present, in the proportion of about 6 to \ y but while Hamilton and others 

 State that stomata do not occur on the upper epidermis, the writer finds that there 

 they exist in ratio to the glands as 4 to \ . In section the lamina shows, inside the 

 upper and lower epidermis, an upper and lower rather loosely arranged palisade meso- 

 phyll. In the upper of these the eells are somewhat more densely packed and are 

 richer in chloroplasts than in the lower. Between them is a spongy mesophyll that 

 is made up of large irregulär cells with few chloroplasts. These cells Surround large 

 intercellular spaces. One median stronger bündle (midrib bündle), two smaller medio- 

 laterals, and 2 — 4 still finer sub-marginal bundles traverse the mesophyll tissue as 

 veins. The entire structure therefore suggests that of a leaf, both surfaces of which 

 are fairly well exposed to light; both develop a roundish-celled palisade mesophyll, 

 though to an unequal degree; and both bear stomata. 



The pitchered leaves are greatly more developed histologically than are the foliage 

 leaves. The distal part of the petiole shows hairs, stomata and glands externally. In 

 section a circular zone of mesophyll surrounds a discontinuous circle of seven bundles, 

 all strengthened and protected externally by scleroid patches. Four of these are infero- 

 lateral, and are somewhat apart from three that are supero-lateral. The former, as 

 they run up toward the pitcher, spread out as the main bundle-tissue of its wall, the 

 latter run into and supply the lid. As the petiole merges into the upper posterior 

 part of the pitcher, the two inferior and median bundles come together and are con- 

 tinued downward along the back and base of the pitcher as its midrib bündle. This is 

 continued upward anteriorly along the median ciliated ridge and slightly within or below 

 the level of its diverging wings. It distributes branches inward across the pitcher wall 

 that fuse with branches from the two next to be studied, and short branches outward 

 into the wings, which are therefore to be viewed as dorso-lateral wings to the median 

 ridge or midrib from which they spring. Just beneath its termination at the tip of 

 the ridge and in front of the pitcher mouth, it gives off strong bundles which run 

 round in the substance of the peristome and fuse with finer bundles from the two 

 laterals. These two laterals, as they emerge from the petiole, branch and run down- 

 wardly or acröss the wall, forming fine connections anteriorly with the midrib vein. 

 In nearly every case the lower and stronger set sweep across the backs of the two 

 "lateral patches" or near them, and supply their huge sunken glands with definite vascular 

 processes (p. 9). The highest set supplies transverse branches to the peristome, 

 along with the diverticula from the median. The three superior bundles of the petiole 

 run upward into the lid, and there divide into many anastomosing branches that becoine 

 fine and rather abundant near the margin. 



The histology of the pitcher was studied in 1 878 by Dickson, and has since 

 been repeatedly examined. The general external epidermis may be colorless but in 

 sun-exposed pitchers its cells contain a deep crimson dissolved pigment. These cells — 

 like most of those over the pitcher wall — show pore canals in the side partitions that 

 suggest intercellular Communications. Numerous stomata and alluring glands are present, 

 the latter appearing, to the naked eye even, as minute specks. Toward the base and 

 posterior part of the pitcher the stomata are less abundant than in front. The exterior 

 surface of the lid is richly provided with stomata and alluring glands, while the unicell- 

 ular hairs here attain their most complex development, since they often show a tertiary 

 thickening outside the brown cell contents. The inner surface of the lid is usually of 

 a crimson color except along the clear radiating whitish areas. Each of its cells is 

 pentagonal to hexagonal, and is prolonged on its outer and inferior wall into a short 

 blunt to tapered down-directed process whose free surface is delicately striated, as in 

 the lid hair-cells of Sarracenia sps. The cells therefore as a whole form a down- 

 wardly overlapping System (Fig. 3 Aa). Attractive lid glands are distributed amongst 

 these, and contrast with the crimson cells from their pale densely-granular contents. 



