Chapter V — 87 — Cephalotus 



in the typical manner — two cover cells surrounded by four others. In 

 slightly larger glands additional cells are intercalated. Their outer 

 walls are seen now to be thick and pitted. The surrounding epidermal 

 cells overlap the shoulder of the flask, and the strong buttress thicken- 

 ings of their radial cell walls stand out {lo — 20). 



The largest glands are to be found in the areas in the "colored 

 patches" as Dickson called them, on account of their deep red color- 

 ing. They differ in no respect beyond that of size from the others. 

 They are spherical in form, with a thick neck and the central mass of 

 something like 150 to 200 cells is surrounded as seen above by a single 

 layer of flat cells with their radial walls suberized, the periclinal walls 

 being of cellulose, thus ensuring a path of diffusion {10 — 19). 



The colored or glandular patches, of which there are two, one on 

 each side of the pitcher, are the most remarkable feature of this species. 

 They are reniform, thickened regions of the wall, the outline being sharp 

 and well marked below and more or less crenate along the upper 

 edge (p — 4). It is a "bolster" (Goebel) of tissue in which the 

 mesophyll is more developed than otherwhere, and projecting in- 

 wardly, showing no sign of its presence on the outer surface. The 

 glands just mentioned are more numerous on the upper moiety, but are 

 by no means confined to it. The epidermis between the glands offers 

 the most remarkable appearance of all in that it is supphed with in- 

 numerable stomata. Dickson (1878) described them as small oval 

 bodies surrounded by two to four other cells. Hamilton remarked 

 that they are "remarkably Kke stomates" but that there is always a 

 wide opening between the guard cells. Dakin (191 8), at that time a 

 member of the staff of the University of Western Australia, visited 

 Albany and there obtained material for study. He saw clearly that 

 these structures are stomata, confirming Goebel's earlier description 

 (1891). It is clear that the guard cells are immobile and that these 

 stomata do not function as such. Goebel called them water pores, 

 pointing out that the pore is plugged by the cellulose membrane of a 

 parenchyma cell underlying it, which would not, of course, prevent the 

 excretion of water. Dakin found that the membrane closing the pore 

 is locally thickened to form a "pad" which he thought acted as a 

 torus that, with changing turgidity of the cell, would open and close 

 the pore, the whole acting as a regulating mechanism. He further 

 thought that the function of the stomata is absorption and suggested 

 that the glandular patches be called lateral absorbing areas {10 — 12). 



I found (19336) that Dakin is correct in his claim that the wall of 

 the underlying parenchyma cell is thickened beneath the pore; but 

 that the thickening is so definitely torus-like as he showed in his figure 

 (191 8, Fig. 11), and especially his interpretations are certainly to be 

 doubted. There is some evidence that the plugging membrane is the 

 result of hydrolysis of the occluding wall and that there is given off a 

 mucilage-hice secretion (Lloyd 19336), but further study on fresh ma- 

 terial obtained at Albany does not strengthen this idea of the matter. 

 The more ready staining of the torus-like thickening is due to the fact 

 that it is not cuticularized as are the guard cells and the epidermis in 

 general, so that cellulose stain (such as methylene blue) attacks the 

 thickening quickly. That, however, these structures are important 



