Our own experience is somewhat to the effect, that there are some few lichens which are doubtful as to whether they are fungi or lichens, but, in by far the majority of cases, there is not the slightest difficulty in determining, from the peculiar firmness and elasticity of the tissues, minute peculiarities which the practised hand can detect rather than describe, and even the general character of the fruit that they differ materially from, though closely allied to fungi. We have only experience to guide us in these matters, but that is something, and we have no experience in fungi of anything like a _Cladonia_, however much it may resemble a _Torrubia_ or _Clavaria_. We have _Pezizæ_ with a subiculum in the section _Tapesia_, but the veriest tyro would not confound them with species of _Parmelia_. It is true that a great number of lichens, at first sight, and casually, resemble species of the _Hysteriacei_, but it is no less strange than true, that lichenologists and mycologists know their own sufficiently not to commit depredations on each other. Contributions are daily being made to this controversy, and already the principal arguments on both sides have appeared in an English dress,[U] hence it will be unnecessary to repeat those which are modifications only of the views already stated, our own conclusions being capable of a very brief summary: that lichens and fungi are closely related the one to the other, but that they are not identical; that the "gonidia" of lichens are part of the lichen-organization, and consequently are not algæ, or any introduced bodies; that there is no parasitism; and that the lichen thallus, exclusive of gonidia, is wholly unknown amongst fungi. The Rev. J. M. Crombie has therefore our sympathies in the remark with which his summary of the gonidia controversy closes, in which he characterizes it as a "sensational romance of lichenology," of the "unnatural union between a captive algal damsel and a tyrant fungal master." [A] De Bary, "Des Myxomycètes," in "Ann. des Sci. Nat." 4 sér. xi. p. 153; "Bot. Zeit." xvi. p. 357. De Bary's views are controverted by M. Wigand in "Ann. des Sci. Nat." 4 sér. (Bot.) xvi. p. 255, &c. [B] De Bary, "Recherches sur le Developpement de quelques Champignons Parasites," in "Ann. des Sci. Nat." 4 sér. (Bot.) xx. p. 5. [C] "Popular Science Review," vol. viii. p. 96. [D] Dr. J. H. Bennett "On the Molecular Origin of Infusoria," p. 56. [E] They have, however, no close relation with real _Torulæ_, such as _T. monilioides_, &c.--COOKE'S _Handbook_, p. 477. [F] Berkeley's "Outlines of British Fungology," p. 24. [G] Berkeley's "Introduction to Cryptogamic Botany," p. 235. [H] Gray, "Notices of Insects which form the Basis of Fungoid Parasites."