NATURE 



[Nov. 2, 1 



and thus representing a most distinct natural family, 

 imitating as it were the Hepatic^ by its quadrifid 

 capsule, but not having any real affinity with that group. 



About 200 new species are described in the present 

 edition, many of them only known in a barren state, and 

 in several instances misgivings are expressed by the 

 author as to their stability. We may glance at some of 

 these en passant. Ephemerum has one new species, E. 

 Rutheanum, and we surmise our Sussex plant {E. inter- 

 medium, Wils., E. ienuine7've, Lindb.) is also distinct. 

 The Eibhemeracece really seem to merit the rank of a 

 natural family rather allied to TricJiostomacea than to 

 FunariacecB, for which the diminutive size, permanent 

 protonema, and leaf structure would supply the chief 

 characters. 



In Weissiacea we find Ancsctangium, a genus which 

 has exercised the minds of most bryologists as to its 

 systematic position, but which perhaps is as happily 

 settled here as is possible. Gyroweisia, Hymenostomton, 

 Oreoweisia, and Rhabdoweisia, standing as sections of 

 Weisia in the previous edition, are now raised to the 

 rank of genera. In Dicranacea we have also 'a new 

 genus — Metzleria — which appears to be very close to 

 Dicranodontitim, and Catnpylopus now includes twelve 

 species, while those of Fissideus number no less than 

 nineteen. LeptotricJium, Hampe, is still retained as a 

 genus, though its author has himself replaced it by the 

 much older name, Ditriclmm, Timm. 



Didymodon and Trichostotnum receive considerable 

 additions, chiefly, however, only known in a barren state, 

 as is also the genus Geheebia, established to receive 

 Tortula gigantea. 



We pass next to the great genus 0)'tJiot}-icliwn,\n'^\C\f:^ 

 we find no less than forty-two species ; so uniform are 

 these in habit and foliage, that they have hitherto 

 proved a most troublesome group to deal with, nor 

 do we find that the nine sections into which it is 

 divided help us readily to determine the species. In no 

 genus of mosses do we require so full a series of speci- 

 mens, for we must have the capsule with its calyptra, and 

 with and without the lid, in order satisfactorily to deter- 

 mine them, and we fear that more species have been esta- 

 blished than will eventually prove tenable. 



Bryum is another genus receiving a large accession of 

 species — no less than thirty-four new ones — and Zieria is 

 still maintained, though used long ago by Sir J. E. Smith 

 for a genus of RutacecB, and therefore altered by Prof. 

 Lindberg to Plagiobryum, which must certainly be 

 adopted. In the Addenda v/e also find a new genus, 

 Merceya, founded on the Eucalypta ligulata of Spruce, 

 but strictly we should say that this name must give place 

 to Scopelophila, Mitten. Another new genus, Anacoha, is 

 also established for Gly pilocarpus Webbii. 



Among Pleurocarpous mosses, Myurclla Careyana does 

 not find a place, although recorded as found in Europe. 

 Thuidiuin_ decipiens, De Not., the author states ,he has 

 not seen, yet it was distributed in Rabenhorst's Bryo- 

 theca under both No. 1,141 and 1,182. It has no relation 

 to the genus Thuyidiu7n, is erroneously described as 

 monoicous, and indeed can only be regarded as one of 

 the many forms of Hypnum commntatum. Of the great 

 tribe Hypnca thirty-six new species are described. 



In the Bryin^ anomaly we find Sphagnum now 



numbering twenty species, grouped in six sections ac 

 ing to Schliephacke's arrangement. These we fancj 

 have to be somewhat reduced, as it now appears t 

 certain that in this family at least, a dioicous and m- 

 cous condition of the inflorescence may occur in 

 same species. 



Neglect of the work of other writers and especial 

 papers in the various botanical journals of this and i 

 countries is the principal shortcoming of the work b 

 us, and probably the author has not had time propei 

 consult them ; in every other respect the Synopsis r 

 tains the high character it had already acquired, fc 

 description of species could be more accurate and p 

 taking, while the paper and printing are superior tc 

 ordinary run of foreign books. 



It will thus be seen that Schimper's Synopsis 

 still continue to be the standard work on the moss< 

 Europe, and fitly comes to us trom an author whose i 

 has been identified with the study of these intere 

 plants for the past forty years. 



OUR BOOK SHELF 



Outlines of Practical Histology. By William Ru 

 ford, M.D., F.R.S. Second Edition. (J. an( 

 Churchill, 1876.) 



When, a year ago, we reviewed this work upon its 

 appearance, it consisted of but seventy-two pages, 

 contained four illustrations ; the second edition ( 

 pies very nearly two hundred pages, and is illust 

 with sixty- three woodcuts. The enlargement gives 

 author an opportunity of entering with conside 

 greater detail into his subject, and he is able to intro 

 much new matter. Among the most important addi 

 we may mention a chapter on the optical principles 

 which the microscope is constructed, including imme 

 lenses, and an instrument manufactured by Mr. Swi 

 London, which is apparently as good as those of c 

 nental celebrity. The histological sections may be 

 practically, to be re-written, for to almost every 01 

 added matter of great value, essential to all but the m 

 commencer. Among these we notice paragraphs 

 the effects of gases on the blood, the enumeration ol 

 discs, the " prickle " cells of the epidermis, lymphatic 

 the diaphragm, coverings of hair, structure of the n 

 and of the cerebral convolutions. In the fourth pa 

 the work, which is devoted to general considera 

 regarding histological methods, the application of vap 

 and gases to tissues is explained, as are the hot stag 

 the microscope, with its heating apparatus and the n 

 chamber of Dallinger and Drysdale. The author's m 

 tome is figured, as is the apparatus necessary for injec 

 tissues by the pressure-bottle. All the figures are 

 cellently drawn, and very lucid, and so greatly has 

 book increased in value, instructive as it was before, 

 we feel quite justified in recommending those who poj 

 the first edition to purchase the second, and those 

 are studying the first principles of practical histolog 

 obtain it without fail. 



A Study of the Rhcetic Strata of the Val di Ledro in 

 Southern Tyrol. By T. Nelson Dale, jun., Memb( 

 the Geological Society of France. Pp. 69, with 1 

 and Sections. (Paterson, New Jersey, 1876.) 



On the western side of the Lago di Garda is situat 

 tract of Secondary rocks which has been comparati 

 little explored by geologists. Lying as it does exactly i 

 the Austro- Italian frontier, this area has neither I 

 described by Stoppani and the Italian geologists, nor 

 it received full justice fro in the officers of the Vie 



