ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 487 



resembling normal cupules, and thus allow the escape of the gemnife. 

 Finally, the author discusses shortly the outer and inner conditions 

 which bring about this phenomenon. He emphasizes the point that 

 here, as in numerous other plant-groups, the relation of organic to 

 inorganic substances may play a part. The possibilities whicli could 

 bring about such a disturbance in nutrition are indicated. 



Fruit-pedicel of Hepaticae.* — Ch. Douin, who in recent years has 

 called attention to the importance of the sporogonium, and especially of 

 the pedicel, as distinctive characters in certain groups or genera of 

 hepaticae, shows that it is necessary to use the results with discretion, 

 and discusses errors which have been made by other bryologists. 

 K. Miiller, for instance, has described the characteristic structure of the 

 pedicel of Gephalozia.fluitans, but unfortunately selected an abnormal 

 pedicel for the purpose. Miiller also figured wrongly the transverse 

 section of the pedicel of Lepidozia silvatica. Douin now figures several 

 sections from a type -plant which show the correct structure. Douin 

 also calls attention to the fact that if tranverse sections of the living 

 pedicel of Cephaloziellacese are cut, four files of large cells are seen ; 

 but if the material is fixed in Fleming's solution, dehydrated and 

 hardened, before being cut, the sections are found to contain four files 

 of large outer cells, and four files of small inner cells. These latter 

 become torn in sections of living material ; and, further, during the 

 rapid growth of the pedicel they also become ruptured and are replaced 

 by a long intercellular meatus. 



New Principles of Systematic Bryolog'y.t — L. Loeske lays down 

 the following principles of systematic bryology : a greater regard to the 

 conditions of life, to the biology ; a rejection of the principle, hitherto 

 maintained, of the greater importance of the sporophyte ; the equal 

 importance of both generations ; also a rejection of the firmly held 

 principle that anatomical characteristics are of greater importance than 

 morphological. Systematic unities, including species, are abstractions, 

 although, in the fixed and but slightly variable species, conception and 

 object may correspond very well. There are no characteristics which 

 can be laid down as " specific," but every group of mosses, down to the 

 species and forms, must be studied and classified according to its 

 particular idiosyncrasy. Critical valuation must be made of all attain- 

 able data for the improvement of the systematic arrangement, which 

 knows no finality. Natural relationship must be brought more pro- 

 minently forward than has hitherto been the case. Systematic arrange- 

 ment is a scientific result which is always capable of improvement. On 

 these principles is based the forthcoming work on the Laubmoose 

 Europas (published by Max Lande, Berlin-Schoneberg). 



* Rev. G6n. Bot., xxviii. (1916) pp. 129-32 (1 pi.). 



t Hedwigia, liv. (1914) pp. 210-16. See also Bot. Centralbl., cxxsrii. (1916) p. 99. 



2 L 2 



