SUPPLEMENT 



53 



4. Ammonia-organisms. These forms develop also in presence of nitrates, 

 but their growth is greatly furthered by ammonia. To this group belong 

 Eurotiopsis, Aspergillus niger, Saccharomyces albicans, yeasts, and Bac. subtilis. 

 With reference to Saccharomyces albicans it is stated (LiNOSSiER, 1890) that 

 it will have nothing to do with nitric acid, and that it develops more feebly 

 with amino-acids than with ammonia ; urea is even a worse nutrient than 

 amino -acids. 



5. Ammo-organisms. Bac. perlibratus, B. typhi, and Rhizopus oryzae 

 thrive better with asparagin than with ammonia ; other amino-acids appear 

 to have a similar effect. 



6. Peptone-organisms. Growth is scarcely perceptible with asparagin or 

 ammonia, and peptone cannot be replaced by proteid. Examples : Bac. 

 anthracis, B. proteus ; lactic-acid Bacteria (BEIJERINCK, 1901). 



7. Proteid-organisms. Micrococcus gonorrhoeae and Bacillus diphtheriae 

 prefer proteid, and do not grow in peptone or other nitrogenous media. In 

 nature, indeed, they are parasites and, strictly speaking, should not be included 

 here. 



Nothing is known as to the mode of manufacture of proteid out of the 

 simpler nitrogenous compounds. We must assume, however, that amino-acids 

 are first formed in this case also, which are afterwards combined into proteid. 

 The fact that amides (urea, acetamide ; SHIBATA, 1904) and amino-acids 

 (RACIBORSKI, 1906) are first of all split up, and that it is only the resulting 

 ammonia that is employed as the source of nitrogen, does not invalidate this 

 hypothesis. Proteid can be formed only out of a number of different amino- 

 acids ; if, therefore, only one be present, then that must be first split up to 

 give rise to the many required. 



The question as to what is a good combination of carbon and nitrogen 

 cannot naturally be answered in general terms. If proteid or peptone be the 

 source of nitrogen the addition of a special source of carbon is often unneces- 

 sary ; this is true in many cases of asparagin. Generally speaking, a culture 

 solution containing peptone and glucose has hitherto been considered as the 

 best medium. 



182, 1. 45, after in them read It is out of our power to give a detailed account 

 of the more recent advances in this interesting department of our subject ; 

 a complete exposition will be found in LAFAR'S Mykologie (1904), by BENECKE, 

 and also in CZAPEK'S Biochemie, Vol. II. 



183, 11. 12-14, for REINITZER . . . humins read further, only part of the 

 humus-nitrogen is assimilable. Possibly, certain ' specialists ' may obtain 

 their supply of carbon from humins, as these researches tend to show. 



1. 31, after to exist read (comp. ITERSON, 1904 ; JONES, 1905). 

 1- 37> f or etherial read ethereal ; for (hadromal, comp. p. 70) read 

 (lignin). 



1. 38, for hadromal read lignin 



184, 11. 7-9, for (on which . . . BRUNSTEIN, 1901) read a list of which is given 

 by H. FISCHER in LAFAR'S Mykologie (I, p. 269) 



1. 32, for Figs. 33-5 read botanical text-books 



I. 33, after (1891-3) read and of FENNER (1904) 



II. 46-7, for Sarracenia . . . with others read epiphytes 



1. 51, after by the plant, read Detailed investigations have still to be under- 

 taken to determine whether the decomposition of the insects caught in the 

 pitchers of Sarracenia is due merely to putrefactive processes or whether this 

 plant should be classed with typical carnivores (FENNER, 1904). 



