﻿346 
  BOTANICAL 
  GAZETTE. 
  [December, 
  

  

  EosoLL 
  has 
  carefully 
  determined 
  a 
  large 
  number 
  of 
  raicrochemical 
  

   methods 
  for 
  the 
  recognition 
  of 
  ghicosides 
  and 
  alkaloids. 
  These 
  will 
  be 
  

   found 
  summarized 
  in 
  a 
  recent 
  pjper 
  printed 
  in 
  the 
  25Lh 
  Jahresberichl 
  de^ 
  

   niederdster, 
  Landes 
  Real- 
  Gymnasiums 
  Stockerau, 
  unfortunately 
  a 
  very 
  inac- 
  

   cessible 
  publication. 
  

  

  Allusion 
  was 
  made 
  in 
  this 
  journal 
  (xv, 
  p. 
  188) 
  to 
  the 
  preliminary 
  

   paper 
  by 
  Dr. 
  Blass, 
  in 
  which 
  he 
  denied 
  that 
  the 
  function 
  of 
  the 
  sieve-tubes 
  

   was 
  the 
  transport 
  of 
  proteids. 
  He 
  has 
  now 
  published 
  his 
  experiments 
  in 
  

   exienso 
  (Prings. 
  Jahrb. 
  21, 
  253-292.). 
  As, 
  according 
  to 
  Heine, 
  the 
  func- 
  

   tion 
  of 
  the 
  starch 
  sheath 
  is 
  to 
  provide 
  for 
  the 
  formation 
  of 
  the 
  bast, 
  so 
  B. 
  

   thinks 
  the 
  true 
  function 
  of 
  the 
  sieve-tubes 
  is 
  to 
  provide 
  nourishment 
  for 
  

   the 
  construction 
  of 
  the 
  xylem. 
  The 
  fact 
  that 
  the 
  sieve-tubes 
  and 
  vessels 
  

   appear 
  simultaneously 
  in 
  the 
  youngest 
  parts 
  of 
  plants, 
  as 
  well 
  as 
  the 
  fact 
  

   that 
  the 
  sieve-tubes 
  show 
  their 
  typical 
  form 
  only 
  in 
  plants 
  with 
  true 
  

   wood, 
  points 
  to 
  reciprocal 
  relations'. 
  Furthermore 
  the 
  structure 
  and 
  con- 
  

   tents 
  of 
  the 
  phloem 
  are 
  such 
  as 
  to 
  indicate 
  a 
  provision 
  for 
  storage 
  and 
  

   radial 
  conduction 
  of 
  proteid 
  materials 
  in 
  the 
  immediate 
  vicinity 
  of 
  the 
  

   cambium. 
  

  

  WoRTMAXN 
  has 
  just 
  published 
  an 
  important 
  paper 
  (in 
  the 
  Bd. 
  M,, 
  

   48,581^et 
  seqq.) 
  on 
  the 
  recognition, 
  occurrence 
  and 
  significance 
  of 
  dias- 
  

   tatic 
  ferments 
  in 
  plants. 
  The 
  present 
  view, 
  that 
  starch 
  is 
  always 
  brought 
  

   into 
  solution 
  by 
  the 
  agency 
  of 
  diastase, 
  is 
  erroneous, 
  he 
  says. 
  Diastase 
  

   18 
  either 
  not 
  present 
  at 
  all, 
  or 
  not 
  in 
  sufficient 
  amounts, 
  in 
  the 
  assimilat- 
  

   ing 
  parts 
  of 
  plants 
  to 
  account 
  for 
  the 
  solution 
  of 
  the 
  starch. 
  On 
  the 
  other 
  

   hand 
  it 
  is 
  found 
  in 
  small 
  quantities 
  (as 
  large, 
  however, 
  as 
  in 
  assimilating 
  

   organs) 
  m 
  starch-free 
  seeds, 
  tubers 
  and 
  roots. 
  W. 
  concludes 
  that 
  dias- 
  

   tase 
  IS 
  a 
  direct 
  derivative 
  of 
  protoplasm, 
  sometimes 
  occurring 
  in 
  small 
  

   quantities, 
  sometimes 
  in 
  large. 
  His 
  experiments 
  go 
  to 
  show 
  that 
  in 
  

   many 
  cases 
  protoplasm 
  itself 
  brings 
  about 
  the 
  solution 
  of 
  starch. 
  There 
  

   IS 
  really 
  a 
  very 
  short 
  step 
  between 
  the 
  cases 
  of 
  such 
  direct 
  action, 
  and 
  

   those 
  in 
  which 
  the 
  protoplasm 
  produces 
  diantase 
  in 
  sufficient 
  quantities 
  

   to 
  etiect 
  solution. 
  When 
  we 
  consider 
  the 
  quantitative 
  and 
  temperature 
  

   relations 
  of 
  the 
  diastatic 
  enzymes 
  it 
  is 
  evident 
  that 
  they 
  ally 
  themselves 
  

   more 
  closely 
  with 
  vital 
  than 
  with 
  chemical 
  substances. 
  The 
  observa- 
  

   T^^'^uv^"? 
  conclusions 
  of 
  W. 
  harmonize 
  well 
  with 
  the 
  investigations 
  oi 
  

   Krabbe 
  (see 
  this 
  journal 
  xv, 
  p. 
  279) 
  on 
  the 
  mode 
  of 
  solution 
  of 
  starcj 
  

   grains 
  by 
  diastase 
  and 
  with 
  Haberlandt's 
  studies 
  on 
  the 
  diastase 
  secretin. 
  

   lunction 
  of 
  the 
  " 
  aleuronedayer 
  " 
  in 
  the 
  seeds 
  of 
  grasses. 
  

  

  