﻿MUSSELS 
  IN 
  TRIBUTARIES 
  OF 
  UPPER 
  MISSOURI 
  RIVER. 
  

  

  13 
  

  

  at 
  the 
  expiration 
  of 
  the 
  period 
  of 
  parasitism; 
  in 
  either 
  case 
  the 
  

   regular 
  or 
  irregular 
  occurrence 
  of 
  flood 
  stages 
  is 
  of 
  considerable 
  

   moment. 
  This 
  factor 
  would 
  more 
  particularly 
  affect 
  the 
  distribution 
  

   and 
  propagation 
  of 
  mussels 
  above 
  the 
  point 
  on 
  the 
  river 
  to 
  which 
  

   fish 
  ordinarily 
  have 
  free 
  access. 
  As 
  a 
  matter 
  of 
  fact, 
  the 
  James 
  

   River 
  is 
  so 
  broken 
  up 
  that 
  this 
  point 
  is 
  comparatively 
  low 
  in 
  its 
  

   course. 
  

  

  There 
  are 
  small 
  milldams 
  at 
  Milltown, 
  Riverside, 
  and 
  Huron. 
  

   These 
  dams 
  are 
  only 
  3 
  to 
  6 
  feet 
  high, 
  but 
  are 
  not 
  provided 
  with 
  

   fishways 
  and 
  are 
  certainly 
  a 
  barrier 
  to 
  the 
  movement 
  of 
  fish 
  at 
  

   ordinary 
  stages. 
  Even 
  without 
  these, 
  the 
  frequent 
  stretches 
  of 
  riffles 
  

   between 
  the 
  more 
  lagoonhke 
  portions 
  of 
  the 
  river 
  would 
  ordinarily 
  

   prevent 
  the 
  free 
  movement 
  of 
  fish. 
  In 
  any 
  event, 
  the 
  fish 
  could 
  sel- 
  

   dom 
  pass 
  above 
  Milltown, 
  and 
  it 
  has 
  already 
  been 
  noted 
  that 
  the 
  prin- 
  

   cipal 
  mussel 
  beds 
  are 
  between 
  Lesterville 
  below 
  and 
  Milltown 
  above. 
  

  

  Average 
  Stages 
  of 
  Water 
  in 
  James 
  River 
  at 
  Huron, 
  S. 
  Dak., 
  prom 
  Obser- 
  

   vations 
  BY 
  the 
  Weather 
  Bureau, 
  Department 
  of 
  Agriculture. 
  

  

  Highest 
  stage, 
  14.6 
  feet, 
  Mar. 
  15, 
  1910. 
  Lowest 
  stage, 
  -0.5 
  foot, 
  Sept. 
  3, 
  4, 
  and 
  5, 
  1911, 
  and 
  Sept. 
  15 
  to 
  

   25, 
  1913. 
  

  

  a 
  River 
  frozen 
  entire 
  month. 
  '< 
  River 
  frozen 
  1st 
  to 
  23d. 
  c 
  River 
  frozen 
  23 
  days. 
  

  

  VERMILION 
  RIVER. 
  

  

  Conditions 
  in 
  the 
  Vermilion 
  River 
  are 
  similar 
  in 
  a 
  smaller 
  way 
  to 
  

   those 
  of 
  the 
  lower 
  James 
  River. 
  This 
  stream 
  is 
  parallel 
  to 
  the 
  James 
  

   River 
  and 
  only 
  20 
  to 
  30 
  miles 
  eastward. 
  

  

  The 
  Vermilion 
  River 
  rises 
  at 
  Lake 
  Herman, 
  Lake 
  County, 
  S. 
  Dak., 
  

   and 
  after 
  flowing 
  about 
  110 
  miles 
  in 
  a 
  southerly 
  direction 
  enters 
  the 
  

   Missouri 
  River 
  just 
  below 
  Vermilion, 
  S. 
  Dak. 
  The 
  uppermost 
  point 
  

   of 
  the 
  river 
  exammed 
  was 
  at 
  Parker, 
  where 
  it 
  is 
  composed 
  of 
  lagoon- 
  

   hke 
  portions 
  2 
  or 
  3 
  feet 
  deep 
  and 
  10 
  to 
  40 
  feet 
  wide, 
  connected 
  by 
  

   narrow 
  riffles, 
  with 
  very 
  small 
  flow 
  of 
  water. 
  Some 
  large 
  white 
  heel- 
  

   splitter 
  shells 
  were 
  observed, 
  but 
  mussels 
  were 
  not 
  abundant. 
  

  

  The 
  river 
  was 
  next 
  examined 
  at 
  Davis, 
  where 
  it 
  flows 
  through 
  a 
  

   trough 
  in 
  the 
  seemingly 
  level 
  prairie 
  from 
  50 
  to 
  60 
  feet 
  wide. 
  At 
  

   an 
  ordinary 
  stage 
  of 
  water 
  the 
  stream 
  is 
  20 
  to 
  30 
  feet 
  wide 
  and 
  1 
  to 
  

   2 
  feet 
  deep, 
  having 
  a 
  gravel 
  and 
  sand 
  bottom. 
  Only 
  a 
  few 
  mussels 
  

   were 
  found. 
  

  

  