194 BROOM -RAPES, BALANOPHORE^, RAFFLESIACE^. 



stratum of vegetable mould. Most of them are the size of a fist, but a few are as 

 big as a head, and then weigh 15 kilogr. and more. The tubercles formed directly 

 by the germinating seeds which chance upon the roots are, by the time they attain 

 to about the size of a pea, already in connection with the wood of the attacked 

 root The cortex and a portion of the wood at the place where the parasite is 

 adnate are absorbed by this root. The tissue of the small tuber-stock is squarely 

 and firmly inserted into the superficial notch thus made in the root, and short, peg- 

 shaped bundles, isolated by the loosening of the wood of the nutrient root, appear 

 to grow into the substance of the parasite. As the tuber increases in size vascular 

 bundles are developed in it also, and these grow towards the said bundles of the 

 host and unite with them. 



No boundary can then any longer be certainly recognized between host and 

 parasite, and the strangest fact of all is that we find, in these bundles, cells 

 concerning which we are not able to decide, even by reference to their shape, 

 whether they belong to the one or to the other. The cells which belong 

 undoubtedly to the wood of the nutrient root have dotted walls; the bundles 

 unquestionably developed in the parasitic tuber exhibit, on the other hand, cells 

 with reticulate thickening, which, when slightly magnified, look as if they were 

 transversely striated. Wherever these pitted and reticulate cells meet, cells are 

 intercalated which do not altogether correspond either to the pitted variety 

 belonging to the host or to the reticulate cells of the parasite, but display a form 

 intermediate between the tw^o. Here and there, too, cell-groups belonging to the 

 parasite are entirely buried in the wood of the foster-root in its growth, and in 

 the older tubers the cellular elements of the two plants there bound together are so 

 involved that it is, as has been stated, impossible to establish any line of demarca- 

 tion between the two. 



By the time the tubers have reached the size of a fist their cortical layer is 

 always solid, corkj?-, and areolated; each of the areas being more or less uniformly 

 angled, as is shown in the illustration below. Some of the more protuberant portions 

 elongate and grow out into short, thick stumps bearing scales all round, each of 

 the little areas having a triangular-pointed scale situated in the middle of it. At 

 this stage of development the entire Lophophytum plant has an extraordinary 

 resemblance to the squamigerous rhizome of a fern, or to a dwarf cycad-tree, 

 stripped of its green leaves; and this likeness is enhanced by the fact that the bark 

 and scales of Lophophytum are dark-brown in colour. From the centre of each of 

 these thick stumps, which often reach a height of 15 cm., there now arises a 

 spadiciform inflorescence. At first it is so thickly covered with ovate lanceolate 

 scales possessing dark-brown, quasi-horny tips, overlapping one another like tiles, 

 that the spadix as a whole looks extremely like an erect cycad-cone. Imagine the 

 surprise of a traveller, who chances upon a spot in the depths of a primeval forest 

 where the ground is occupied by Lophophytum, upon seeing hundi-eds of these 

 brown, scaly cones grow up suddenly, in the course of a night following some days 

 of rain, from the subterranean roots of the trees. A day or two later, this gardea 



