312 Oliver. — On Sar codes sanguined, Torr. 
logical differentiation than where a normal metabolism exists ; 
and processes of a complex nature — as for instance the endo- 
genous development of lateral roots — may gradually, in the 
general degradation, give place to simpler methods. My own 
view, however, is that here the exogenous root-branching is an 
advantageous variation that has been perpetuated. 
As regards the relation of the roots of Sarcodes to the 
substratum : — from notes kindly communicated by Mr. Elwes 
no direct connection would appear to exist between them 
and the pine-roots among which Sarcodes grows. The plant 
vegetates amongst decaying portions of the pines, leaves and 
the like, and possesses nothing of the nature of haustoria or 
parasitic attachments. No doubt Sarcodes resembles Mono - 
tropa in this respect, and, as in this case, although the roots of 
the saprophyte come into very intimate relation with the 
roots of other plants, still they are never organically united h 
I have been at some pains to ascertain whether Monotropa 
roots ever form haustoria, and for this purpose have examined 
many specimens of M. glabra from beech- and of M. hirsuta 
from pine-woods, without meeting with a single case to sup- 
port the view of parasitism. Not infrequently I found the 
1 In view of the prominent position now held among botanists by the Mycorhiza 
question, it may not be without interest to call attention here to the observations 
of certain British naturalists of a past generation, more especially as they have 
been quite lost sight of in the recent discussion of the matter. In the years 
1841-2 a lively discussion was running in the pages of the now defunct 
‘ Phytologist.’ Ed. Lees (p. 97) speaks of ‘a hirsuture that appears like a byssoid' 
fungus ’ on the roots of Monotropa. This ‘ hirsuture’ he considered to be a portion 
of the Monotropa plant, which he regarded as a parasite. Wm. Wilson (1. c., 
p. 148) failed to discover any parasitic attachments, and considered the ‘byssoid 
growth’ as certainly no part of the plant. A little later (1. c., p. 297) we find 
Ed. Newman speaking of the ‘byssoid growth’ as an essential part of the plant, 
thus agreeing with Lees in that point. He differs from Lees, however, in denying 
its parasitic habit. Finally, T. G. Rylands, in a detailed paper (1. c., p. 341), ends 
the discussion. His paper is illustrated with a number of woodcuts. The 
‘ byssoid substance,’ he says, ‘ is really fungoid, and performs no essential function 
in the economy of the Monotropa' He detected three types of Fungi — Sepedonium, 
Epiphagos, and Zygodesmos , the last characterised by buckle (geniculated) hyphae. ! 
Hence it appears that although the anatomical relations of the Monotropa roots 
were long ago familiar to naturalists, the view as to the symbiotic nature of 
mycorhiza is essentially modern. 
