AFFINITIES OF BALANOPHOREÆ. 3 
suggested doubtfully by Richard, who however adopted those of * radix," * tuber," and 
* caulis :” it is the “axis” of Griffith; “rhizome” and “caudex” of Geeppert; “ basilar 
receptacle” of Junghuhn, &c. In mode of origin and development it sufficiently accords 
with the definition of a rhizome, as usually employed in descriptive botany. In speaking 
of the root, I wish always to be understood as referring to that organ of the plant upon 
which the parasite grows. : 
The simplest and at the same time most frequent form assumed by the rhizome of Bala- 
nophoreæ, is that of a simple or branched tuber, sessile on the root from which the plant 
derives its nourishment, and giving off one or more flower-bearing peduncles. In the 
earliest stage at which I have examined any of the species, the young plant appears as a 
cellular mass, nidulating in the bark of the root (but partially exposed), with whose cellular 
tissue its own is in organic adhesion, though easily distinguishable. 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 considerable 
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 appear- 
ance. 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 formed in it. For illustrations of these stages of deve- 
lopment see Plates IV. & VI. våg 
. 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. Of this, Lophophytum and perhaps Scybalium are examples. 
The fully formed rhizomes are roughly divisible into the simple, or merely forked or 
lobed, and those which are cylindrical, elongated horizontally and branched; forms which, 
though exceedingly dissimilar, and associated with very important anatomical details, are 
not accompanied by such modifications of the floral organs as would afford sectional 
characters in the Order; as a comparison of Helosis with its very near allies, Seybaliwm, 
&c., proves. The elongated rhizomes of some species form attachments by their ramifi- 
cations to the various roots they encounter; and such never have foliaceous appendages, 
except at the bases of the peduncles or flowering branches. The amorphous or simple 
rhizomes again are often provided with scales (as in Cynomorium, Lophophytum, and 
Spherorhizon) , or with cellular papillæ (as some species of Balanophora). These papillæ 
consist of simple or divided extruded masses of cellular tissue traversed by a furrow ; they 
are very numerous and cruciate in B. dioica, and are probably intimately connected with 
the aération or respiration of the plant; they present nothing remarkable in structure, 
and resemble the rimæ with swollen lips on the spongy bark of some Venispermee, Vitis, 
and many other plants*. 
_ * Junghuhn says (Nova Acta, xviii. Suppl. p. 223) that B. globosa is a species which he never found bearing these 
papillæ, except when it grew on the same root with B. elongata, when, like that species, it was always provided with them. 
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