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nothing has yet been adduced to detract from the correctness of Darwin's conclusions. In connection with this subject, we wonld refer to a work by Hanstein and A. Braun on the parthenogenesis of Cælebogyne ilicifolia, in which, as we understand, Hanstein thinks the parthenogenesis is proved. The subject of Insectivorous Plants has been discussed in numerous papers, among which we may mention an article by Batalin in Flora on the “Mechanism of the Motions of Insectivorous Plants." It is evident, however, that the cream of the subject is to be found in Darwin's work on the subject; and the articles which have lately appeared are beginning to seem a little drawn out. A son of Mr. Darwin has made observations on the protoplasmic filaments protruded by the hairs of Dipsacus; and Cornu, in the Comptes Rendus, mentions having seen the protoplasmic contents of a cell in a fungus pass directly through the cell-wall.
Ferns and Mosses. Systematic works on the higher cryptogams have not been very abundant during 1877. Cesati, in the Proceedings of the Neapolitan Academy, has two papers on the higher cryptogams of Borneo and some Polynesian islands. J. G. Baker describes some ferns of the Andes in the Journal of Botany; and Professor Harrington, of Michigan University, describes some new species collected by Professor Steere. Perhaps the most important general work on higher cryptogams published during the year is the “Cryptogamic Flora of Silesia,” under the direction of Professor Cohn, of Breslau. The vascular cryptogams are arranged by Dr. Stenzel, the mosses and liverworts by Dr. Limpricht, and the Characece by the late Professor A. Braun. The latter portion is particularly worthy of commendation. A second volume, including the algæ by Cohn, and fungi by Dr. Schroeter, is said to be in press. In Flora, Dr. Franks has a paper on the mosses of the northern part of Bavaria, and Jach has an article on Hepaticce in the Botanische Zeitung, in which he criticises the views and determinations of Dumortier.
In regard to the development and morphology of the higher cryptogams, there have been several interesting discoveries. Dr. Berggren, of Lund, has published in the Botaniska Notiser a preliminary notice of the germination of
Azolla, studied by him in New Zealand. Although long studied, the mode of germination of Azolla (which, according to Dr. Berggren, resembles that of Pilularia) had escaped detection. Stahl, in the Botanische Zeitung, describes the process by which the stalks of the spore-cases in mosses, when cut across, may produce protonemata. The same subject is more elaborately treated by Pringsheim in his Jahrbuch; and he gives, in concluding, his views of the nature of the prothallus in the higher cryptogams. Leitgeb has continued his researches on the morphology of Hepaticæ, to which, for some years, he has paid special attention.
Fungi. On no branch of botany is the annual literature more voluminous than on this. The magazine articles in which new species have been described are far too numerous for special mention. In Hedwigia articles have appeared by Magnus, Schroeter, Von Thümen, Niessl, and others; and in Grevillea by far the larger number of articles by English botanists relate to fungi. In the Annales des Sciences is a series of mycological essays by Sorokin, who has also published something in Tledwigia. In England, a translation of Rostafinsky's “Myxomycetes," at least so far as the British species are concerned, has been made by M. C. Cooke. The first volume of Fries's “Icones Hymenomycetum" has been successfully finished. A useful synopsis of the Ustilaginec, by Professor Fischer von Waldheim, has been published in the Annales des Sciences; and the same author has also distributed a paper on the species of Entyloma, and a list of the plants on which the species of Ustilaginece are parasitic. Dr. Wilhelm, of Strasburg, has also distributed his doctorate thesis on the species of Aspergillus. Special mention should be made of some developmental works on fungi. Brefeld's Basidiomycetes forms the third part of his series published under the name of “Ueber Schimmelpilze." Brefeld is the strongest advocate of the view that, so far as at present known, the fruit of the Basidiomycetes is not produced from a carpospore. In a short article, Brefeld also discusses the theory that fungi do not require light to attain perfection, and brings forward several facts to show that such is not the case-at least, not universally; for some species will not bear spores until they are exposed to the light. In a paper on the species of Entomophthora, the same writer states that the fungus described by Cohn, in the "Beiträge zur Biologie,” under the name of Tarichium is only the resting-spore stage of Entomophthora radicans. In concluding, he presents a new view of the classification of fungi, which, while some will complain of it as being too speculative, is in some respects an improvement on the ordinary classification. Dr. Hermann Bauke, in a thesis on the “Nature of Pycnidia,” shows, by means of cultures, that the view of Tulasne was in the main correct, and that the pycnidia are in most cases states of different Sphæriacere, although he admits there are a few cases where the reverse is the case. “The Nature of Spermatia” has formed the subject of a paper by Cornu in the Annales des Sciences. He denies that the spermatia are male organs, because he has succeeded in making them germinate, which, as he thinks, proves that they are forms of stylospores. The low group of fungi (or, if you please, algæ) the Chytridiacece has of late been a favorite field of study; and new species and genera are described with uncomfortable frequency. In the second part of Volume II. of the “ Beiträge zur Biologie,” Dr. Nowakowski describes a new species, Polyphagus euglence; and Sorokin, in the Annales des Sciences, has a paper on the vegetable parasites of the Anguillule. The subject of fermentation has been studied by Brefeld in a third paper, in which he states that Mucor racemosus and M. stolonifer produce alcoholic fermentation, although to a much less marked degree than the yeast plant.
Lichens. New species of lichens have been described by Crombie in England, and by Nylander and Arnold on the Continent. The discussion as to the nature of lichens has been carried on by Winter and Minks in the different numbers of Flora, and Nylander has in the same journal some notes on the different forms of Gonidia. The discussion between Drs. Winter and Minks is acrimonious and even abusive, and the botanical public can hardly be said to feel much interest in this personal matter. A very important paper, in two parts, has been published by Dr. E. Stahl. In the first part, the structure of the organs of fructification in lichens is discussed.
Stahl regards the spermatia as male organs, in opposition to the view of Cornu above stated, and he finds them attached to a trichogyne-like organ. This is confirmed by Mr. George Murray in the case of Collema pulposum in the Journal of Botany. Stahl believes that the process of fertilization in lichens is
similar to that in the Floridece, or red seaweeds. In the second part, Stahl relates his experience in cultivating lichens from the spores in connection with free gonidia. The species studied were Endocarpon pusillum, Thelidium minutulum, and Polyblastia rugulosa. The first two species Stahl was able to cultivate until they produced new spores. He also succeeded in making Thelidium grow upon the gonidia of Endocarpon. This is the first successful attempt to produce the fruit of a lichen by sowing the spores with gonidia; and Stahl's experiments go far towards strengthening the view of Schwendener that lichens are fungi parasitic on certain algæ. It is announced that hereafter, in Just's Jahresbericht, the lichens will not be kept as a separate department, but merged with the Ascomycetes.
Algæ. A paper by Dr. Wittrock on the “Development and Systematic Arrangement of the Pithophoraceæ" gives the characters of an order of green alge, which closely resemble the Cladophorce. A series of papers by Dr. Kjellman on the algæ of Spitzbergen, Nova Zembla, and other northern regions is an important contribution to our knowledge of the arctic marine flora. In Nova Zembla, Dr. Kjellman remarks the almost entire absence of a litoral vegetation. Algæ from the Adriatic have been described by Hauck in the Austrian Journal of Botany. A well-prepared set of algæ, principally fresh-water, from Sweden, by Nordstedt and Wittrock, has been offered for sale. In the way of development of algæ we have to mention a careful paper by Janczewski, in the Proceedings of the Cherbourg Society, on the “Development of the Cystocarp in Florideæ.” The development of Botrydium granulatum has been studied by Rostafinsky and Woronin, and it is described and figured in the Botanische Zeitung. This plant finally produces zoospores with two cilia which conjugate with one another; but there are also, in some stages, zoospores which do not conjugate. The development of Acetabularia Mediterranea, which was only partially known, has been completed by Professors De Bary and Strasburger. The bodies which were called spores are shown to produce zoospores, and a peculiar basal process of the thallus is described. Reinke, in Pringsheim's Jahrbuch, has described the growth of the thallus in certain Phæosporæ, and has also studied the development in Zanardinia collaris, where, as he says, the mass which is to form the spore comes to rest before being fertilized. A somewhat acrimonious discussion has appeared in the columns of the Botanische Zeitung between Reinke and Rostafinsky with reference to the credit to be assigned to their different papers on the terminal growth of Fuci, reported in last year's Record.
Bacteria. The literature of Bacteria and related forms has not been quite so voluminous as last year. A substantial paper, by Warming, has appeared in the Copenhagen Proceedings, in which there are described and figured several of the Danish monads, Bacteria, Beggiatoc, etc. The investigations of Tyndall with regard to the sterilization of liquids have been important. Sterilization, or the reduction to a state of inactivity or torpidity of the germs of minute vegetable organisms, is, according to Tyndall, better accomplished by repeatedly raising the fluid to the boiling-point, and allowing it to remain there but an instant, than by prolonged boiling.
In General. The changes which have taken place in the botanical chairs have been more numerous than usual the present year. The deaths of Alexander Braun, Hofmeister, De Notaris, and Parlatore left vacancies in the chairs of Berlin, Tübingen, Rome, and Florence. The chair of Berlin has been filled by Eichler, of Kiel. At Tübingen, Professor Schwendener, of Basle, replaces Hofmeister; and Pfeffer, of Bonn, is transferred to Basle. At Florence it is reported that Beccari is to have the chair filled by Parlatore. Professor J. E. Areschoug, of Upsala, having resigned, his place has been filled by Professor T. M. Fries. The chair of Aberdeen having become vacant by the resignation of Professor Dickie, Mr. J. W. H. Trail has been appointed in his place. Millardet, formerly of