ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 697 



albumen in the seed is decomposed by hydrolysis ; the first substauces 

 formed are albumoses aud peptons ; these are, however, not stored up, 

 but break up into amido-acids and hexon-bases, in addition possibly to 

 asparagin and glutamin. The substances thus formed are again decom- 

 posed, with formation of ammonia, and from this are produced asparagin 

 and glutamin in the presence of glucose. These amides are, therefore, 

 at least for the most part, not products of decomposition, but rather the 

 first products of synthesis. 



Indigo Fermentation.* — According to M. W. Beijerinck, the sub- 

 stance from which indigo is formed is not identical in all indigo-plants. 

 In the " indican-plants " (Indigofera, Polygonum tinctorium, Phajus 

 grandiflorus), this substance is indican, the glucoside of indoxyl; while 

 in the " indoxyl-plants " (Isatis tincloria) it is indoxyl itself. In all 

 cases the indigo-pigment is formed, directly or indirectly, by the oxidation, 

 of indoxyl. In the indican-plants the indican is found in the colourless 

 protoplasm, while the indican-enzynie is located in the chloroplasts. The 

 organisms which decompose the indican effect this in two different ways. 

 In the smaller number it is broken up by an enzyme ; in others it is split 

 up directly without the intervention of an enzyme, through the activity 

 of the protoplasm. 



Fermentation of Saccharides.! — According to Fischer each saccha- 

 ride should have its special ferment, and this view is supported by certain 

 yeasts which hydrolyse maltose and not saccharose or trehalose. M. E. 

 Dubourg, however, finds that all yeasts secrete all the diastases of all 

 the saccharides. To show this, the ferments are cultivated in nutritive 

 media rich in nitrogenous matter with a mixture of glucose and of the 

 saccharide. Under these conditions there is fermentation, not only of 

 the glucose but also of the second sugar. The author has worked with 

 numerous species of yeasts, more or less active, and has always obtained 

 alcohol with maltose, saccharose, raffinose, and trehalose, but not with 

 lactose. Mucor olternans ferments only maltose and trehalose. The 

 phenomenon of hydrolysis appears to be general among yeasts, but it is 

 not so with the Mucorinese. 



7. General. 



Dust from Drift-Ice.J — Heir P. T. Cleve has made a microscopical 

 examination of four samples of dust from drift-ice north of Jan Mayen, 

 brought by the E. Greenland current. Some of them were very rich in 

 siliceous organisms, belonging almost without exception to diatoms, 

 including a large number of species, both fresh-water and brackish or 

 marine, the latter both litoral and plankton. The only other organisms 

 recorded are a few spores of Flagellata, and a fragment of a doubtful 

 Tertiary fossil. 



B. CRYPTOGAMIA. 



Cytology of Non-nucleated Organisms.§— Dr. A. B. Macallum gives 

 the following as the summary of his observations, made chiefly on 

 Saccharomyces, Beggiatoa, and the Cyanophyceje. 



* S.B. k. Akad. Wetensch. Amsterdam. Sept. 30th, 1899, and March 31st 1900 

 See Bot. Ztg., lviii. (1900) 2" Abt., p. 18S. 



t Proces-verbaux des se'ances Soc. des Sci. Phys. et Nat. de Bordeaux, Anne'e 

 1898-9, pp. 28-9. 



t Ofv. k. Vetensk.-Akad. Forhandl. Stockholm, Ivii. (1900) pp. 393-7 (English) 



§ Trans. Canadian Inst., vi. (1899) pp. 439-503. 



