ing to the supposition that this latter mycelium must be produced by a reproductive organ different from the Uredo.

It has been observed in many instances, that where the nutrient plant is perennial the mycelium of the parasite remains barren in the tissue of the stem or rhizome, aud pushes out its fertile ramifications into the organs of annual duration.

The conclusions which Dr. De Bary draws from the above observations, and which he propounds by way of answer to the questions stated at the outset, are as follows:-" Endophytes are not produced from the metamorphosed substance of diseased plants. They originate from germs which penetrate healthy plants, and develope a mycelium. The latter infests either the entirety of the nutrient plant, or is confined to definite portions of it. It produces fruit which (according to the species) is situated indifferently upon any part of the nutrient plant, or confined to certain organs of the latter. Each species of parasite has its own mode of growing in the nutrient plant; each sort of germ has its own special mode of penetrating the tissue and selecting the point of penetration. There are numerous species analogous in their mode of penetration and growth, whilst other species, nearly allied in organization, differ considerably in that respect. Each species of parasite has certain special nutrient plants. It is even probable that in certain Uredine with multiple fruit, and alternate generations, each sort of reproductive organ buries its germs in a different nutrient plant. Experiments prove with certainty, that the vegetation of the parasite is the sole cause of those diseases of the nutrient plant, which are connected with the parasite's appearance. There is no pretence for the supposition that a morbid predisposition of the individual nutrient plant causes or favours the attack of the parasite. On the contrary, the more healthy a plant is, the more the parasite flourishes, provided it meets with external conditions favourable to its vegetation. All the diseases in question are contagious, and the contagion is propagated by means of the numerous germs of the parasites, provided the external conditions are favourable. These conditions vary with the species, and it is because the study of these conditions has been neglected, that results have been obtained which appear to disprove contagion. The observations which have seemed to some authors to prove an individual predisposition on the part of certain plants to the attacks of a parasite, or to a disease to which the latter owes its origin, have been made on peren

They are

nial plants, which the parasite permanently infests. explained by the fact, that the mycelium embedded in these plants is itself perennial.

Lastly, there are endophytes which are little injurious to the plants which they inhabit. There are some which pierce the cells without effecting any immediate alteration in the membrane, the nucleus, or the contents of the cells. The point of entry easily escapes observation, and the aspect of these cells has given rise to the erroneous opinion that fungi can grow in the interior of perfect cells and originate directly from the contents of these cells.

We may state, that at the end of the paper Dr. De Bary adds a synopsis of the Peronosporeæ, which will be of great service to Mycologists desirous of investigating the species of this genus of Moulds.

LIV. TULASNE AND DE NOTARIS ON FUNGI.

(1.) SELECTA FUNGORUM CARPOLOGIA, ETC., junctis studiis ediderunt L. R. Tulasne, Ac. Sc. Par. etc. Socius et C. Tulasne, M.D. Tomus secundus. Xylariei, Valsei, Sphæriei. Folio, Paris, 1863, pp. xx. et 320. Tab. xxxvi.

(2.) SFERIACEI ITALICI per G. De Notaris. Centuria Prima. Folio min. Genova, 1864. pp. 90.tab. xxv.

WHEN Persoon's Synopsis was published at the close of the last century, it was said justly, so far as the state of Mycology at that time was concerned, that he had placed the science on a new basis, a praise which more modern discoveries have not been able completely to overthrow. His later publications, and more especially his Mycologia Europæa, added but little to his reputation. Indeed, so superficially did he examine matters at last, that we have seen an elder-leaf sprinkled with spots of whitewash which he had supposed to be caused by some mould, and which he had sent to Desmazières for information, a fact comparable only with the notion of an eccentric French botanist, that the spines of Cucumbers were a sort of Sphæria, and with our finding in the herbarium of a continental botanist of some repute a piece of lemon-peel, which had been dropped accidentally in a wood, figuring as a new species of Sphæria, the glandular dots having been taken for perithecia.

Fries, ever ready to acknowledge the merits of his predecessors, was content, so far as nature would allow, to tread in Persoon's footsteps. He had not the whole arrangement of Fungi to reform as Persoon had, but still a great deal of work lay before him, and taking nature as his guide, he referred many genera of doubtful affinity to their right places; and in such genera as Agaricus and Sphæria, he reduced heterogeneous masses into natural groups, many of which now remain either as distinct genera or families. He was, perhaps, too much biassed in some matters by his own peculiar philosophical views, and sometimes led astray by them. It must, however, always be remembered, in judging of his earlier publications, that they were prepared before the modern improvements of the microscope, a circumstance which perhaps has induced him throughout to lay less than its proper stress upon characters derived from microscopic observations. A comparison of Dr. Greville's beautiful figures of Fungi in the Scottish Cryptogamic Flora, with the magnified analyses, will show how little accuracy was arrived at as regards minute structure with the old compound microscopes. Fries, however, had not merely an extraordinary degree of tact, insomuch that he often arrived at truth by a sort of intuition, without the proper materials for logical induction, but he had an exquisite eye for nature, and in consequence, in spite of many appearances to the contrary, he saw in the course even of his early studies the intimate connection of many genera of Fungi, apparently the most distinct, as of Tubercularia with both dark and coloured Sphæriæ, Cytispora with other species of the same group, Fusarium with Peziza, &c., while he proved or pointed out that a considerable portion of generally received genera, were founded merely on young, imperfect, or abnormal conditions of various Fungi. While he thus weeded out a whole host of mere mycelia or monsters, he drew attention to the fact that in many fungi there is more than one form of fruit, a fact at which he certainly did not arrive by any profound microscopic research. The prejudice, however, against such views was then so overpowering, that feeling that he was in advance of his day in these respects, he contented himself often with merely hinting an opinion, and, as he says, he was sometimes in an obscure matter advisedly obscure. He saw, indeed, occasionally the better way, but by free choice, in accordance with popular feeling, followed the worse. His reputation as a mycologist, perhaps, would have been altogether compromised, and his works thrown on one side, to the

fatal discouragement of a mind rather sensitive as to unjust criticism, had he followed out his own views to their proper ends. This was reserved for others, who, possibly, might not have arrived so early at the truth, without his previous hints.

We may, perhaps, be excused for just pointing out, by the way, the bearing which this fact-as to the career of one of the first thinkers of our day, for Fries has been justly regarded by first-rate authorities as one of the master-spirits of the age, though his attention has been confined principally to a comparatively obscure department of science—has upon certain theological difficulties which very needlessly agitate some sensitive minds.

The Systema Mycologicum was completed much about the time that fresh light was thrown on many matters of minute structure. The true formation of the Hymenium in the higher Fungi had hitherto been scarcely noticed, though an attentive examination of the figure of Coprinus comatus in the Flora Danica, published several years before the close of the eighteenth century, would have led at once to correct notions. A false interpretation of Micheli's figures and Sturm's erroneous analysis deferred for some years the more truthful doctrine. About the same time Leveillé and Berkeley published their memoirs on the subject, and this was one great step towards a right appreciation of affinities. The analysis of Puffballs and Phalloids naturally followed: Elaphomyces, hitherto associated with the former, was shown to be allied rather to the Truffles; Nidularia, and afterwards Sphærobolus, no longer held an uncertain position, and a few other genera assumed their proper rank and station, whose relations could not be ascertained without the use of a good microscope.

Another step, however, was now made towards ascertaining the true affinities of many forms which had hitherto remained doubtful. It became more and more clear that, in very many fungi, there were two and sometimes several modes of fructification; and the truth of Fries' suggestion of the identity of many genera, at first sight most distinct, was at least passed over without discussion. The subject indeed was taken up, in a more or less fragmentary manner, by several mycologists, but it was reserved for the two brothers Tulasue to make such genera an especial study, and one or two excellent German observers have followed successfully in their track. The Tulasnes have now for twenty years worked together in perfect unison, the inimitable sketches of the one concurring with the learn

ing of the other to make mycology take its place as one of the most interesting branches of Botany. The figures which accompany their numerous works have all the neatness and delicacy which have so long characterised the botanical drawings which adorn French works of science, but far exceed in truth and execution all their predecessors, and in none is their peculiar excellence more apparent than in the two volumes, one of which we have undertaken to notice.

It is, moreover, to the Tulasnes more especially that we are indebted for one of the most important discoveries in mycology, viz., that of the real nature of the so-called spores in the Uredines, and of the close affinity in consequence which exists between them and Tremella-an affinity indicated indeed by the hand of nature, through the gelatinous parasites of the species of the genus Juniperus, but scarcely appreciated even by Fries-and one, it may be observed, which was more or less obscured by prevalent notions adopted by Unger and others of his countrymen as to the equivocal nature of these productions, to which Fries, to the detriment of science, gave unfortunately too willing an ear. Prevost had, indeed, shown something of this nearly half a century before; but his observations, like those of Fries, were in advance of his age, and were in consequence almost entirely neglected, till they were at a recent period rescued from oblivion by the advance of science.

This, however, was not the only point of great importance the first discovery of which was due to Prevost, for he ascertained the production of zoospores in Cystopus, a discovery which has been revived only within the few last years. Carus, indeed, a very short time after Prevost, hit upon something of the same kind in Saprolegnia, but the relation of these productions to Fungi was not generally recognised till the publication of De Bary's papers placed it beyond doubt. The existence of distinct sexual organs in these curious productions, first observed by Pringsheim, has been confirmed by the same talented observer, and it now appears that they are not confined to the Saprolegnia, whose peculiar habit might perhaps be admitted as an argument for their occurring in that group only, so long as other Fungi seemed to be totally deprived of them. The nature of the bodies called Spermatia, which occur so frequently amongst Lichens and Fungi, is extremely problematical; but it now appears that in the genera Cystopus and Peronospora, sexual organs are almost as clearly demonstrable as in the group just mentioned, while Hofmeister believes that similar organs exist in Truffles,