BROOM-RAPES, BALANOPHOREH, RAFFLESIACES. 199 
Balanophoreze in consideration of their coalescence with the roots of their hosts, 
only three species are known. Two of them (Hydnora Africana and H. triceps) 
belong to South Africa, the third (Hydnora Americana = Prosopanche Bwrmeisteri) 
to South Brazil. The tuber is represented by a prismatic body with from four to 
six angles furnished with papille along the edges. The flower-buds which burst 
from it have at first the form of spherical Gasteromycetes, but gradually elongate 
and assume the form of a large fig or upright club. This structure opens at the 
thickened- upper extremity by three stout fleshy valves representing petals. At 
the base of this curious flower no appendage is to be seen that could be interpreted 
as a bract or leaf. The fleshy mass of flowers evolves a disagreeable putrid odour, 
and in this property the Hydnorez resemble the Rafflesiz, which belong to the 
next group of parasitic Phanerogams. 
The fifth series of flowering parasites is composed of the Rafflesiacex, plants 
connected with Balanophorex and Hydnorez by their general aspect, the absence 
of chlorophyll, and the undifferentiated embryo which consists merely of a group of 
cells. They used all to be classed together under the name of Rhizanthez; but the 
Rafllesiacese are now treated as a separate family on account of the characteristic 
structure of their flowers and fruit. The formation of these organs will again come 
up for discussion later on when we treat of the wonderful structure of the famous 
giant-flower Raflesia; at present we are only concerned with the relationship of 
the parasite to the food-providing host-plant. This is, if possible, even more 
remarkable than in the case of Balanophorew and Hydnorex. In the latter the 
union is effected within a structure like a tuber or a rhizome, the vessels and cells 
of the parasite coalescing with the exfoliated and disordered wood-cells belonging 
to the root or stem of the host-plant; whereas in Rafllesiacee the embryo, having 
penetrated beneath the cortex of the host, produces a more or less definite hollow 
cylinder which surrounds the wood of the host’s root or stem (as the case may be), 
and constitutes a sort of vestment intercalated between the wood and the cortex of 
the host. There is no production of tuberous enlargements as in the Balanophoree. 
The stem or root attacked by the parasite only exhibits a moderate thickening at 
the place where the parasite dwells beneath the cortex, and the cortex itself is only 
destroyed at the spot where the embryo pierces through it, and where subsequently 
the flowers emerge. When roots constitute the substratum whereupon the parasite 
has established itself, they are always of a kind that run throughout upon the 
surface of the ground; when stems are chosen for attack, they are either the 
branches of trees or shrubs, shoots clothed with dead foliage belonging to dwarf 
suffruticose bushes, or else woody lianes of tropical forests. The seeds are con- 
veyed to the host-plants through the intervention of animals. 
Rafflesias are found in the haunts of elephants and along the tracks followed by 
those beasts. The Rafflesia-fruits are accordingly no doubt trampled upon and 
crushed, and the little seeds imbedded in the pulpy mass of the fruit thus have an 
opportunity of adhering to the elephants’ feet. The seeds are afterwards rubbed oft 
by projecting roots at places more or less remote from the original locality, and if 
