158 CELLULOSE. 



Amhhjstegium has undergone revision, and has annexed Hypnum 

 Jilicinum. Thiddmm decipiens De Not. must be sought for under 

 Hypnum Notarisii BouL, in the section Cratoneuron. I am not aware 

 of the description of any new species, save the Orthotrichum quoted 

 above. Dklymodon Camusi, sp. n. (p. 80), is suppressed in the Sup- 

 plement, as it turns out to be Diphysciumfaliosiun var. acutifoliwn. 

 Among misprints I notice that ^' piriforme" and " Braithwaite's 

 Moos-Flora" occur several times. Schimper's error in quoting 

 Tortida vinealis var. nivalis Spruce as var. ylacialis is copied under 

 Geheehia yiynntea. Owing to insufficient lettering of plates 17 and 

 125, Brachyodus trichodes and Blindia trichodes are likely, from 

 their close affinity, to cause confusion among inexpert students. 



Valuable as M. Husnot's addition to bryological literature and 

 iconography undoubtedly is, it might have been made even more 

 satisfactory by fuller bibliography and synonymy, by a glossary, 

 and (as already stated) by definite notification of the degree of 

 enlargement of the figures. j,^ Gepp. 



Cellulose ; an outline of the Chemistry of the Structural Elements of 

 Plants with reference to their Natural History and Industrial 

 Uses. By Cross and Bevan. 8vo, pp. 320 ; with 14 plates. 

 London: Longmans & Co. 1895. Price 12s. net. 



This book is what it professes to be — a bringing together of 

 "the scattered contributions of investigators, with more especial 

 reference to the work of the past fifteen years." It either tells all 

 that is known about the chemistry of cellulose and its derivatives, 

 or sends us to the original papers for full details ; and though 

 necessarily of a very special nature, contains useful hints for the 

 broader-minded plant-physiologist. The subject matter falls into 

 three parts. Part i. deals with the typical cellulose and the 

 cellulose groups, i.e., what the botanist calls "cellulose." In 

 Part ii., on "Compound Celluloses," are considered those sub- 

 stances resulting from the processes commonly known as lignifi- 

 cation, suberisation, and conversion into mucilage. Part iii., "Ex- 

 perimental and Applied," contains valuable hints on method, and 

 supplies stimulus to more extended research. The " applied " portion 

 is of a more general mterest. Apropos of paper, the authors regret that 

 there is in this country (and we might surely add, on the Continent) 

 no public opinion on the subject of paper in use for books and 

 records. Those, at any rate, which have more than a passing value 

 should be committed to pages suitably resistant both to chemical 

 and mechanical wear and tear, that is, to those composed of the 

 normal and resistant celluloses only; e.y., cotton and linen, and 

 not to those of which oxy-compounds, like wood-celluloses or 

 esparto- and straw-celluloses, form part, or which contain in ad- 

 mixture with the above ligno-cellulose in the form of wood pulps. 

 Messrs. Cross and Bevan have had their own book printed "upon 

 a paper carefully selected, as composed of the normal celluloses," 

 and the excellency of the result justifies their choice. 



The fourteen plates, reproduced from photographs of sections, 

 are to illustrate the general features of structure and arrangement 



