﻿482 
  Scientific 
  Intelligence. 
  

  

  that 
  the 
  supply 
  of 
  combined 
  nitrogen 
  obtained 
  by 
  the 
  green 
  

   plant 
  is 
  ultimately 
  derived 
  from 
  the 
  free 
  nitrogen 
  of 
  the 
  atmos- 
  

   phere, 
  and, 
  secondly, 
  that 
  the 
  supply 
  is 
  not 
  obtained 
  from 
  the 
  

   atmosphere 
  directly 
  by 
  the 
  leaves, 
  but 
  indirectly 
  by 
  the 
  roots 
  

   through 
  the 
  soil. 
  Nor 
  can 
  there 
  be 
  much 
  doubt 
  that 
  the 
  tubercles 
  

   are 
  associated 
  with 
  the 
  process 
  of 
  the 
  assimilation 
  of 
  the 
  free 
  

   nitrogen 
  : 
  but 
  it 
  is 
  a 
  question 
  whether 
  this 
  process 
  takes 
  place 
  in 
  

   the 
  tubercle 
  itself, 
  or 
  whether 
  it 
  is 
  not 
  carried 
  on 
  in 
  the 
  soil 
  by 
  a 
  

   Schizomycete, 
  which 
  may 
  either 
  be 
  derived 
  from 
  the 
  tubercles, 
  or 
  

   be 
  an 
  independent 
  organism. 
  It 
  seems 
  probable 
  that 
  the 
  latter 
  

   suggestion 
  is 
  nearer 
  the 
  truth. 
  It 
  is, 
  in 
  fact, 
  known 
  that 
  a 
  bacte- 
  

   rioid 
  organism 
  exists 
  in 
  the 
  soil 
  having 
  the 
  property 
  of 
  forming 
  

   nitrogenous 
  compounds 
  from 
  free 
  nitrogen 
  in 
  the 
  presence 
  of 
  non- 
  

   nitrogenous 
  organic 
  substance 
  (e. 
  g. 
  glucose). 
  It 
  may 
  be 
  that 
  the 
  

   development 
  of 
  this 
  organism 
  is 
  especially 
  favored 
  by 
  the 
  presence 
  

   of 
  the 
  tubercular 
  roots 
  of 
  the 
  Papilioneee 
  in 
  the 
  soil, 
  and 
  that 
  the 
  

   nitrogenous 
  substances 
  which 
  it 
  produces 
  are 
  absorbed 
  by 
  the 
  

   roots 
  after 
  having 
  undergone 
  nitrification. 
  

  

  "The 
  tubercles 
  are 
  structures 
  formed 
  by 
  the 
  hypertrophy 
  of 
  

   the 
  cortex 
  of 
  the 
  root, 
  resulting 
  from 
  the 
  attack 
  of 
  the 
  fungus 
  at 
  

   various 
  points: 
  their 
  cells 
  are 
  rich 
  in 
  sugar 
  and 
  starch: 
  the 
  

   branches 
  of 
  the 
  mycelium 
  penetrate 
  most 
  of 
  the 
  cells, 
  and 
  there 
  

   bud 
  off 
  innumerable 
  gemmules 
  (sometimes 
  called 
  bacterioids). 
  

   The 
  tubercle 
  eventually 
  becomes 
  disorganized; 
  the 
  gemmules 
  are 
  

   then 
  set 
  free 
  into 
  the 
  soil, 
  and 
  are 
  doubtless 
  the 
  means 
  by 
  which 
  

   other 
  roots 
  become 
  attacked 
  by 
  the 
  fungus." 
  

  

  The 
  subjects 
  following 
  are 
  remarkably 
  well 
  treated: 
  the 
  trans- 
  

   fer 
  of 
  water, 
  and 
  movements. 
  g. 
  l. 
  g. 
  

  

  2. 
  Cellulose. 
  An 
  outline 
  of 
  the 
  Chemistry 
  of 
  the 
  structural 
  

   elements 
  of 
  plants, 
  with 
  reference 
  to 
  their 
  Natural 
  History 
  and 
  

   Industrial 
  Uses 
  ; 
  by 
  C. 
  F. 
  Cross, 
  E. 
  J. 
  Bevan, 
  and 
  C. 
  Beadle. 
  

   8vo., 
  pp. 
  320. 
  London 
  and 
  New 
  York 
  (Longmans). 
  — 
  For 
  many 
  

   years 
  the 
  two 
  chemists 
  whose 
  names 
  are 
  first 
  in 
  the 
  order 
  above 
  

   given, 
  have 
  been 
  associated 
  together 
  in 
  the 
  practical 
  investigation 
  

   of 
  cellulose. 
  Their 
  contributions 
  to 
  the 
  literature 
  of 
  the 
  subject 
  

   have 
  been 
  numerous, 
  but 
  these 
  publications 
  have 
  been 
  widely 
  

   scattered 
  and 
  hence 
  partially 
  unavailable 
  to 
  American 
  students. 
  

   The 
  present 
  work 
  brings 
  together 
  such 
  of 
  their 
  results 
  as 
  may 
  not 
  

   properly 
  be 
  regarded 
  as 
  trade 
  secrets, 
  and 
  it 
  embodies 
  a 
  good 
  

   deal 
  of 
  the 
  voluminous 
  literature 
  of 
  the 
  whole 
  subject. 
  Some 
  of 
  

   their 
  remarkable 
  discoveries, 
  especially 
  in 
  regard 
  to 
  the 
  cellulose 
  

   thiocarbonates, 
  are 
  incorporated 
  into 
  the 
  body 
  of 
  the 
  work 
  with- 
  

   out 
  even 
  a 
  reference 
  to 
  the 
  important 
  fact 
  that 
  science 
  owes 
  these 
  

   recent 
  acquisitions 
  mainly 
  if 
  not 
  wholly 
  to 
  them. 
  To 
  the 
  botanist 
  

   the 
  monograph 
  possesses 
  a 
  high 
  degree 
  of 
  interest, 
  since 
  the 
  

   typical 
  cellulose 
  and 
  the 
  three 
  compound 
  celluloses 
  are 
  adequately 
  

   discussed 
  from 
  all 
  points 
  of 
  view. 
  The 
  most 
  important 
  phases 
  

   presented 
  are 
  the 
  following 
  : 
  (1) 
  the 
  colloidal 
  aspects 
  of 
  cellulose, 
  

   (2) 
  the 
  relation 
  of 
  vegetal 
  to 
  animal 
  cellulose, 
  (3) 
  new 
  methods 
  of 
  

   acting 
  on 
  the 
  compound 
  celluloses. 
  While 
  the 
  treatise 
  is 
  of 
  value 
  

  

  