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lump, (see fig. 1). Lookiug carefully, however, over the mass of roots 

 and soil I had brought away, I observed numerous young plants which 

 seemed to promise greater facilities in the examination. These I ac- 

 cordingly worked at very patiently, but still, at the base of each ap- 

 peared what to the naked eye seemed hard granules of soil mixed up 

 with hairy radical fibres of beech. Expecting that maceration in wa- 

 ter would remove this hard matter and expose the roots of the Mono- 

 tropa, I steeped them in water ; but to my surprise they remained as 

 hard and intractable as before. On applying a lens to solve this mys- 

 tery, it became fully evident that these hard hairy knobs were in fact 

 parasitical nidi attached to the roots of the beech, and deriving their 

 sustenance from them. Having now obtained a clew, I found that the 

 hairy knobs on the beech-roots were of all sizes, from that of a pea, 

 fi'om which the little embryo Monotropa was sprouting, to that of a crab, 

 nourishing a full company of several plants, (see the figures).* These 

 parasitical knobs, which constitute the nidi from which the Mono- 

 tropa springs, are formed on the extreme radical fibres of the beech, 

 but I was able to trace their connection with the thicker roots, and 

 they were evidently composed of the swollen fibres agglomerated to- 

 gether, and so covered with a brown hirsuture, that to the eye they 

 looked like lumps of compact soil. The larger knobs had the same 

 aspect when examined with a lens, so that they, no doubt, increase in 

 size every year, as additional sustenance is required by the multiply- 

 ing plants ; for when a single plant has once established itself on its 

 parasitical attachment, numerous offsets soon arise from the parent 

 plant, (see fig. 1). At the same time, as the juices are concentrated 

 in the knob, and it increases in size, so do the fibres about it ramify- 

 in complexity on all sides, and send forth their spongioles in every 

 direction, so that the parasitic mass, like the mistletoe, always has an 

 abundant magazine at command. These hairy parasitical nidi ap])ear 

 to me most analogous to the moss-balls formed by the Cynips Kosae 

 on roses and sweet-briars, except that while the latter, being formed 

 for the nourishment and habitation of insects, only endure for a sea- 

 son, the former are perennial. 



I have shown, I think satisfactorily, that the hairy vesicular knobs 

 that I have discovered, are seated on, and of necessity nourished by, 

 the radical fibres of the beech, connected as these are with the rami- 

 fications of larger roots. As the Monotropa springs from and derives 

 its nourishment through the medium of these nidi, which increase in 



* I observed, also, many very minute nodules on the beech-roots, where the embryo 

 plant was as yet not apparent. 



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