RAFFLESIA ARN'OLDf. 413 



I may liereafter have an opportunity of entei'ing fully [-232 

 into the question whether Kajjleslacccn and Balanophoreo' 



received several names, as vasa porosa, puncfata, vasiform cellular tissue, 

 dotted ducts, &c., and which are so conspicuous in the majority of arborescent 

 Phocnogamous plants, have never been observed in any part strictly belonf^ing 

 to these parasites. But even adniittinc: the non-existence of the large vessels 

 liere referred to, their absence will hardly be regarded as a sufficient reason for 

 the union into one class of tiie two families in question, especially when it is 

 considered — 



First. That conformity in vascular structure, even when accompanied by 

 peculiarity of tissue, does not always indicate, much less determine, botanical 

 affinity. This is strikingly exemplified in Conifercc and Winteranea>, two 

 families which, though so nearly agreeing in the uniformity and peculiarity of 

 their vessels, and in both of whicli the large tubes referred to are wanting, yet 

 differ so widely from each other in their organs of reproduction and in their 

 leaves, that they may be regarded as placed at opposite extremities of the scale 

 of Dicoti/ledoiies. 



Secondli/. That uniformity of vascular structure is not always found in 

 strictly natural families. Thus many tropical woody^ climbers exhibit remark- 

 able peculiarities of vascular arrangement not existing in the greater part of 

 the families to which they respectively belong, but which peculiarities appear 

 to have no inlluence whatever in modifying their reproductive orfrans. 



Thus also in Myzodcndron^ the whole woody tissue consists of vasa scalari- 

 forinia, a peculiar structure, and very different from that of all the other genera 

 belonging to Loranthacecc, to which this genus has been referred, and to which, 

 though it does not absolutely belong, it is nearly related. Even this peculiar 

 structure of the stems of Myzodendron admits of considerable modifications in 

 the different species of the genus, which is strikingly exemplified in comparing 

 the loose vascular tissue with large and singularly constructed medullary ravs 

 of M. brachi/stuchyum and quadrijlorum witii the more minute vessels and ex- 

 tremely narrow rajs of J/, imnctulatnm. 



I may also notice that in TUlandsia nsneoides, as well as in the nearly related 

 species of that genus, the capillary stems are destitute even of spiral vessels, 

 though in Brorneliaccce generally the ordinary vascular system is found. 



Whatever may be the state of vessels in the fully developed parasites belong- 

 ing to RaJlesiaceiP, it appears to me that at least RaJ/fesia in its very early 



1 Mi/zodendron of Banks and Solander, from /ly^sw or fxv^u) sier/o, and <}kv^oovy 

 lias been changed to Misodendron by De Candolle and all following systematic 

 writers; no doubt merely from a mistake as to the intended derivation. Mi/zo- 

 dendron, hitherto referred to Loranthaceoi, to which it is certainly closely allied, 

 especially through Aiiddap/uie of Poeppig, appears to me to have characters 

 sufficient to distinguish it as, at least, a suborder or tribe {Myzodoidrccc), 

 namely, the structure of its ovarium, in which it approaches to Santalacece, 

 having three ovula suspended from the apex of a central placenta, only one of 

 which ripens; the entire absence of floral envelope in the male; the singular 

 feathery appendages of the female flower and fruit compensating in the dis- 

 persion and subsequent adhesion of its seeds, which are destitute of that 

 viscidity existing in those of the parasitic Loranthacece. ; and lastly, the embryo 

 being undivided, with its dilated and exsertcd radicle enclosed in a semi- 

 transparent covering, a continuation of the membrane lining the cavity of the 

 albumen in which the cmbrvo is lodged. 



