Parasitical Plants. — The Balanophoracece. 349 



probably occur in nearly equal proportions. The rhizome, or 

 rooting portion of Balanophorous plants is usually in the form 

 of a simple or branched tuber, seated fiat upon the root of the 

 plant, to which it is attached. In very young plants the 

 appearance is nothing more than a mass of cellular tissue, 

 united with the tissue of the root. Dr. Hooker says, " It offers 

 at first no trace of a vascular system, nor any distinction of 

 parts, but before it has reached the cambium layer of the 

 bark, and before its upper extremity has attained any con- 

 siderable size, an opaque line of white cellular tissue, different 

 from the rest, may be found in the centre of the mass, or 

 beneath each of its lobes, in which vascular tissue makes its 

 appearance. Shortly afterwards the wood of the root upon 

 which the parasite grows appears to become affected, its annual 

 layers are displaced, and at a still later period vascular bundles, 

 enclosed in a cellular sheath, are found in the axis of the 

 rhizome, and are continuous with those already found in it. 

 Some genera do not present the appearance of any vascular 

 bundles communicating with those of the root stock, but their 

 own vascular bundles may be traced descending to the line of 

 union between the root and the parasite, where they become 

 closely applied to the vascular system of the former, without, 

 however, forming any interlacement or organic union." 



The roots or rhizomes of these plants are of comparatively 

 slow growth, but vary much in the several species. This may 

 in some measure be referred to the different forms of attach- 

 ment or union with the roots upon which the parasites grow, 

 for it would appear that there are three distinct modes of 

 attachment in the several distinctive forms or genera, and 

 these have been suggested as lines by which to divide the 

 Bahmojphorce into three sections ; firstly, where the vascular 

 tissue of the parasite and nourishing plant is apparently merged 

 in one, or continuous ; secondly, where the attachment is alone 

 effected by means of the cellular system ; and thirdly, where 

 the termination of the vessels from the root into the parasite 

 are definite or distinct. The most perfect examples of the first 

 of these divisions are to be found in the genera Bhopalocnemis 

 and Balanopliora itself, where also the most perfect vascular 

 system exists, the woody tissue being present throughout the 

 whole plant. Fig. 1 shows a transverse section of B. involu- 

 crata. The formation of the tissue in Helosis Mexicana illus- 

 trates the second division, Fig. 2 ; while that of Langsdorffia 

 illustrates clearly the third, Fig. 3. 



In the cellular tissue of many of the Balanophorce, wax is 

 secreted in large quantities. A view of one of these cells, 

 burst open, and discharging its waxy granules, is shown at 

 Fig. 4. The wax is found mostly in Balanophora and Langs- 



