392 



NATURE 



■ ui iniiii'. 



^A :»/!,... I <.ti 



i.rw».;-.iiv protected 

 I'Up food 



skin ..f 



I. .,1- 



Ml 



1... Ill, Ml . 



- , -. - ..I iliin-u .1..- '. 



M.lKh ..-lU Ml! 



lullMli.il li\ ill' 



llurk-\v,.ll,.| ;, 1 . u- 



1(111. (■11^ Willi- 



mit ^l.'ii'c li ^;i am.' 



\\ ll ■ 11 III! .i^l' I 



111. <iis l..u! 

 ,1 l.snr K- 



^w.-lliiiii I 



I 1.. 



r.-nl' ■ ■ : .ll 



h;iio\' 51 



rillow- ... . si,.,,.^iun, 

 ami -.1 prevents 

 riipuir.' ol tlio seed 

 (■o\.'rini,'s. Intrrn- 

 all\, th.- (.11 walls 

 n <■ a I- .■ > 1 In 1 h .■ 

 sruii-lluni su.ll anil 

 (lisint. ;;iat.', a 11 il 

 this actiiin sK,\\l\ 

 s|)r.a(ls 1 1) |- o u <4 h 

 ill.- f 11 (1 (1 s p e r in. 

 Within about ten 

 days the cell walls 

 throughout the whole length of the corn are modified. 

 The endosp'^rm, in ron<;rqu»'nrf, Ix^romo* soft and mealy 

 instead of h.inl. and it .an h.- hrok.-n and luMnd h.-i\veen 

 the fingers. Tlus staj^.' of niealin.-s^ i^ ihai d.-sir.d h\ the 

 ni.ilisii I. At the same time, thi- sianh i4ianul" - witiiin the 



c-ils l..i:iii to be 



;. 3. — Longitudinal Section of the Germ End 

 of a Barley Corn (Highly _ Magnified 1. 

 " Plum," plumule ; " rad," radicle ; " sscut,' 

 •tcutellum; "ab ep," absorptive epithelial 

 layer. (After Holzner.) 



arr.-l.-d b 



drvini 



Fig. 4.— Section of Portion of Endosperm of 

 a Barley Com (Highly Magnified). 

 .^1 Coverings of the cjrn. B, Aleurone 

 cells containing no starch. C, Thin- 

 walled starch-containing cells comprising 

 the greater part of the endosperm. The 

 starch granules are visible lying em- 

 bedded m the remains of the cell proto 

 plasms. 



llv malt. 



Hfow n and Morris 

 found that ih. srui. !- 

 lum of th.- t^rowiiii; 

 i-mt>r\() ^,ii,i.- t\\(i 

 i-n/\ m.-s, 1 \ las.- and 

 di.isias.-. which bianii 

 about the cliani^cs 

 (1. sciib.-d, whcffas 



th.- .ndosp.-rtii is 

 iiit'it and williout 

 lif.-. l..ii.r . \peri- 

 m.'iiis b\ Hrown and 

 I'.si-omli. conlirmed 

 th. cont.-mion of 

 Haberlandt that the 

 cells of the aleurone 

 layer also secrete the 

 same enzymes. 



At various stages 

 of the malting process 

 the nitrogenous com- 

 pounds originally pre- 

 sent in the endosperm 

 migrate to the 

 embryo. These 

 changes are due to 

 the action of two other enzymes, a peptase and a tryptase. 

 Probably these originate in the same parts of the corn as 

 cytase, but direct evidence on this point is still wanting. 



NO. 2203, VOL. 88] 



tive porn 



ibstaia. s 



splavfd by the skin: it 



il <hliirirl<-, ai etic a< id, 



through, 



aim ion of 



-^ ll. i.-iili- i-.f most funda- 

 iii with jdant ( h<-mislrv. 



'"".i.'- 



her •■n/\ 1: 



Is, Ills ( 



'ili;.-n'-. 



,J.-. 

 Ml 



. (jini)usiii(in ot III. 



>und malt, and tlv 

 Linp.! .11111 ■ .ii,.i .iiii.i.K.M (ij ill.- |ji..(.->s are all (-■••'■' --f 

 primi import.m. .-. l"or the moment, however, w 

 coni-.-rn. ll with the naturi- of th<- transformation- 

 It is not \.-l forts 

 m.altos.-, and show.-d li 



formed from starch by i' -last.-. The new field 



opened up by this dis i numerous investi- 



gators, but, notwithstanding; in. ;r ..ibnurs, the essential 

 point-< are still in dispute: tin- (.institution of the starch 

 mo|.(ul.- and th" mann"r of its br.-.ikdown are still far 

 from b. in^ s.-iil,-d. 'Ih.- qu.-sti(.n is i,,(. complicated for 

 discussiop, h.-r. other than from its mor. i.-clinical aspect. 



Fig. 5. — Diagram of Transverse Sections of Dry and 

 Steeped Barley Corns. A, Dry corn. B, Steeped 

 com. 



Hidwn and Morris hav.- shown that .among th-:' prcxlucis 

 of a star( li ( (uiv-rsion p'-rfortii'd at temperatures much 

 the same as th> br.-w.-r choosrs in practice, are certain 

 unfcrmentable nuiltodcxtrins. If the nrodiu ts from the 

 starch consisted of maltose and stab! only, the 



maltose would be entir- ly ft rment.d wery, and 



tlv b.'.r obtained would be highly alcoluilic and very thin 

 in p:ilat. tlavour. More important still, it would contain 

 no carbohxdrat. material suitable for undergoing the 

 secondary f.rm. ntation ( lianges in the cask or bottle. 

 Such mat. rial is supplied by the m.Tliod.-Mrins. which. 

 th()Ui.jh not fermentable durini; tlie y .uimt. 



are slowly fermented by the secondai ■ >\hicli 



develop in beer when in cask or bottle, and give to good 

 beer its characteristic qualities. 



/•" 



•ides in the 



"s famous 



\istence of 



in organism 



Science has undoubtedly ma(.ie 

 elucidation of the fermentation p 

 investigations, in which he dem. 

 anaerobic life, led him to fi^.i: i \ • ast 

 endowed with two modes of iii. . When air was present 

 it lived the life of an ordinary fungus and exhibited th-- 

 usual actions of cell life ; in the absence of air it took on 

 the new properties of a ferment, and attacked sugar. Thi- 

 view persisted for many years, until .Adrian Brown showed 

 that, in malt wort, yeast cells increase until a definite 

 number are present in a given volume: they then cease 

 reproducing. This prop. ••\ .f ^ n~t is independent of the 

 food supplv. and n , ork with a constant 



number of yeast conditions, it was 



found that oxygen. lar irom arresting the fermentative 



