﻿LOBSTER 
  AND 
  CLAM 
  INVESTIGATIONS. 
  211 
  

  

  Any 
  facts 
  bearinf^ 
  on 
  the 
  length 
  and 
  variation 
  of 
  the 
  time 
  required 
  

   for 
  reaching- 
  the 
  period 
  of 
  sexual 
  maturity 
  in 
  animals 
  should 
  be 
  of 
  

   scientific 
  interest. 
  The 
  conditions 
  determining 
  the 
  length 
  of 
  this 
  

   period 
  are 
  known 
  in 
  few 
  animals, 
  and 
  speculations 
  like 
  those, 
  for 
  

   example, 
  on 
  the 
  meaning 
  of 
  the 
  duration 
  of 
  their 
  life 
  can 
  not 
  safely 
  be 
  

   indulged 
  in 
  without 
  man}^ 
  more 
  facts 
  of 
  this 
  nature. 
  It 
  certainly 
  seems 
  

   to 
  be 
  true 
  in 
  this 
  case, 
  as 
  in 
  that 
  of 
  the 
  accelerated 
  growth 
  and 
  matu- 
  

   rity 
  of 
  03'sters 
  in 
  French 
  claires, 
  and 
  of 
  the 
  .young 
  starfish 
  studied 
  by 
  

   Mead 
  '', 
  that 
  the 
  amount 
  of 
  food 
  determines 
  whether 
  the 
  period 
  shall 
  be 
  

   long 
  or 
  short. 
  The 
  question 
  of 
  the 
  growth 
  of 
  clams 
  has 
  a 
  severel}^ 
  

   practical 
  side 
  also. 
  In 
  any 
  attempt 
  to 
  rear 
  them 
  for 
  commercial 
  pur- 
  

   poses, 
  rapidity 
  of 
  growth 
  is 
  the 
  most 
  important 
  thing 
  to 
  be 
  considered. 
  

   On 
  it 
  depends, 
  to 
  a 
  large 
  extent, 
  the 
  practicability 
  of 
  culture 
  methods. 
  

  

  Many 
  years 
  ago, 
  when 
  the 
  oyster 
  suppl}^ 
  began 
  to 
  decline 
  in 
  Chesa- 
  

   peake 
  Ba}', 
  and 
  an 
  increasing 
  demand 
  caused 
  prices 
  to 
  rise, 
  the 
  life 
  

   history 
  and 
  habits 
  of 
  the 
  form 
  were 
  studied 
  and 
  various 
  methods 
  of 
  

   artificial 
  culture 
  devised. 
  These 
  have 
  been 
  practiced 
  for 
  some 
  time 
  

   with 
  great 
  success 
  on 
  the 
  north 
  Atlantic 
  coast. 
  It 
  is 
  found 
  that, 
  under 
  

   favorable 
  conditions, 
  a 
  marketable 
  size 
  is 
  reached 
  after 
  a 
  growth 
  of 
  

   three 
  or 
  four 
  years. 
  In 
  Europe 
  this 
  period 
  is 
  sometimes 
  shortened 
  to 
  

   a 
  considerable 
  extent 
  by 
  improving 
  the 
  food 
  supply. 
  Great 
  profits 
  

   arc 
  realized, 
  even 
  when 
  that 
  length 
  of 
  time 
  is 
  consumed 
  in 
  awaiting 
  

   the 
  harvest. 
  

  

  The 
  period 
  of 
  growth 
  in 
  the 
  soft 
  clam 
  is 
  much 
  shorter 
  than 
  this. 
  

   A 
  gi'owth 
  of 
  two 
  3^ears, 
  under 
  fair 
  conditions, 
  should 
  produce 
  a 
  clam 
  

   of 
  marketable 
  size, 
  and 
  culture 
  methods 
  are 
  very 
  much 
  simpler 
  and 
  

   cheaper. 
  

  

  THE 
  DECREASE 
  IN 
  THE 
  SUPPLY. 
  

  

  For 
  nearly 
  a 
  quarter 
  of 
  a 
  century 
  the 
  clam 
  supply 
  of 
  the 
  north 
  

   Atlantic 
  coast 
  has 
  been 
  steadily 
  declining. 
  During 
  the 
  last 
  five 
  years 
  

   it 
  has 
  fallen 
  otT 
  very 
  rapidly, 
  and 
  in 
  many 
  places 
  the 
  industry 
  is 
  nearly 
  

   destroyed. 
  

  

  In 
  the 
  report 
  of 
  the 
  U. 
  S. 
  Fish 
  Commission 
  for 
  1894, 
  statistics 
  are 
  

   given 
  showing 
  the 
  production 
  of 
  clams 
  in 
  New 
  England 
  from 
  1880 
  to 
  

   1802. 
  These 
  tables 
  are 
  valuable, 
  because 
  the}^ 
  indicate 
  a 
  great 
  decrease 
  

   in 
  the 
  market 
  sales, 
  and 
  in 
  a 
  case 
  like 
  this 
  it 
  is 
  impossible 
  to 
  obtain 
  sta- 
  

   tistical 
  evidence 
  of 
  the 
  condition 
  of 
  the 
  beds 
  in 
  any 
  other 
  way. 
  Yet 
  

   statistics 
  are 
  not 
  always 
  conclusive. 
  In 
  this 
  case, 
  for 
  example, 
  the 
  tables 
  

   for 
  the 
  State 
  of 
  Maine 
  show 
  an 
  increase 
  in 
  the 
  production 
  from 
  1880 
  

   to 
  1887, 
  in 
  the 
  former 
  year 
  318,383 
  bushels 
  being 
  marketed, 
  and 
  in 
  

   the 
  latter 
  year 
  608,780 
  bushels. 
  From 
  that 
  time 
  until 
  1892 
  they 
  indi- 
  

   cate 
  a 
  stead}^ 
  decrease 
  to 
  416,806 
  bushels. 
  But 
  there 
  was 
  not 
  so 
  great 
  

  

  a 
  Twenty-ninth 
  Annual 
  Report 
  of 
  the 
  Commissioners 
  of 
  Inland 
  Fisheries 
  of 
  Rhode 
  Island. 
  1899. 
  

  

  