SUPPLEMENT 47 



P. 162, 1. 30, after recently read (GENAU, 1901) 



M- 43~5> f or [Mucilage . . . 1903] read It must be classed with the mannates 

 and galactates of the seed, and consists of hemicelluloses, which can be trans- 

 formed into mannose and galactose, but which contain much more water than 

 the corresponding substances in seeds (HERISSEY, 1903). 



163, 1. 13, for amido-compounds . . . also occur read several amino-acids, 

 similar in composition to those which occur in seedlings, are also found (comp. 

 SCHULZE, 1904), 



I. 17, for amido-compounds read amino-acids 



II. 34-5, for of the wood fibres ... in spring read of the cortical and 

 phloem parenchyma, and often also of the wood fibres 



1- 37, f or amides read amino-acids 



164, 11. 3-11, delete From a comparison . . . inactive. 



1. 40 P. 165, 1. 8, for present say ; it will . . . higher plants read present 

 say. As we have seen, diastase, generally speaking, transforms starch into 

 maltose, i.e. a reducing disaccharide which is, by hydrolysis, broken up into 

 two molecules of dextrose. We have already seen that dextrose is formed 

 from starch by the action of certain diastases, and it might well be that we 

 were really dealing with a maltase mixed up with the true diastases. That 

 yeast possesses such a ferment has been definitely proved, but to what extent 

 it occurs in higher plants is still doubtful. Cane sugar is closely related to 

 maltose ; it splits on hydrolysis into one molecule of dextrose and one of 

 levulose, and a splitting of this nature has also been often shown to occur 

 in the germination of the beetroot, where doubtless the cane sugar is trans- 

 formed into invert sugar. Further, the ferment invertase, essential to this 

 splitting, has been proved to exist in various plant organs with sufficient cer- 

 tainty (comp. GREEN, 1899), e.g. in the leaves of Tropaeolum, the buds of 

 trees, seedlings of barley, and in pollen grains, and so one can scarcely doubt 

 that that invertase is widely distributed. It must not be supposed, however, 

 that cane sugar is never employed directly. 



165, 11. 14, 18, 19, for amides read amino-acids 



I. 38, after BUSCAGLIONI read 1899 



II. 40-2, delete and it would . . . dispersed. 



166, The matter of Lecture XIV is continued as part of the preceding lecture. 

 1. 52, after (1897 read comp. CZAPEK, Biochem. II. 209. 



167, 1. 7, for amides read amino-acids 



1. 31, after leaf read and one must believe that proteid as well as amino- 

 acids take part in the migration, probably after first undergoing hydrolysis. 



169, 11. 1-26, for lies in roots . . . but we must read lies partly in the external 

 layer of the protoplasm and partly also in the cell -wall. The important part 

 played by certain cell-walls in preventing the exit of materials from the plant 

 has been emphasized recently both from the anatomical (A. MEYER and his 

 pupils) and the physiological point of view (WACHTER, 1905 ; BROWN, 1907). 

 From WACHXER'S researches it would appear that slices of onion and beetroot 

 lying in water allow quantities of the cell contents to escape, while no extru- 

 sion of material worth mentioning takes place from the uninjured plant into 

 damp soil. It is improbable that the actual wounding induced alteration in 

 the permeability of the protoplasm ; on the contrary, it may be regarded as 

 certain that the waxy cuticle of the onion and the corky covering of the beet- 

 root must act as preventative agents. Since, however, the cell-walls of 

 young roots are very permeable, it must be the duty of the protoplasm to pre- 

 vent a loss of material by diosmosis. According to WILLFARTH (1906) part of 



