﻿SOLAR 
  PHYSICS 
  AND 
  LOCUST 
  INCREASE. 
  83 
  

  

  and 
  Argynnis 
  Lathonia 
  seem 
  confined 
  to 
  the 
  southern 
  counties 
  of 
  Eng- 
  

   land, 
  not 
  ranging 
  north 
  of 
  Peterborough, 
  but 
  that 
  Vanessa 
  Antiopa 
  is 
  

   most 
  plentiful 
  between 
  the 
  Humber 
  and 
  the 
  Tyne.'^ 
  From 
  this 
  the 
  

   writer 
  would 
  infer 
  'Hhat 
  if 
  Daplidice 
  smd 
  Lathonia 
  come 
  to 
  us 
  from 
  

   France, 
  Antiopa 
  more 
  probably 
  comes 
  from 
  I^f 
  orway. 
  I 
  believe 
  there 
  is 
  

   much 
  in 
  this 
  argument, 
  and 
  I 
  surmise 
  the 
  ^Oamberwell 
  Beauties' 
  may 
  

   come 
  to 
  us 
  semi-torpid 
  with 
  deals 
  from 
  Norway." 
  It 
  still, 
  however, 
  

   should 
  be 
  noticed 
  that 
  twelve 
  years 
  out 
  of 
  thirty 
  that 
  this 
  butterfly 
  has 
  

   been 
  taken 
  the 
  records 
  appertain 
  solely 
  to 
  the 
  southern 
  counties, 
  and 
  

   that 
  in 
  1873 
  and 
  1874, 
  years 
  succeeding 
  a 
  great 
  migration, 
  it 
  was 
  plen- 
  

   tiful 
  enough 
  in 
  parts 
  of 
  France 
  and 
  North 
  Germany. 
  In 
  1842, 
  a 
  year 
  

   when 
  Daplidice 
  was 
  taken 
  near 
  Dover, 
  several 
  examples 
  were 
  found 
  

   simultaneously 
  in 
  Belgium/^ 
  a 
  country 
  where 
  it 
  generally 
  occurs 
  but 
  

   siugly. 
  Lathonia 
  again 
  was 
  frequently 
  seen 
  in 
  Jersey 
  from 
  1870 
  until 
  

   1872^2^ 
  a 
  circumstance 
  which 
  seems 
  to 
  afford 
  a 
  reason 
  for 
  connecting 
  in 
  

   a 
  series 
  the 
  captures 
  made 
  in 
  this 
  country 
  during 
  that 
  period. 
  As 
  re- 
  

   gards 
  distribution 
  : 
  in 
  1858, 
  1872-'73, 
  and, 
  as 
  is 
  stated, 
  in 
  1861, 
  Antopia 
  

   visited 
  the 
  east 
  of 
  Scotland, 
  and 
  in 
  1865, 
  1872, 
  and 
  1875 
  it 
  was 
  taken 
  

   in 
  Ireland. 
  Duriug 
  the 
  years 
  1847, 
  1852, 
  1857, 
  1862, 
  and 
  1877 
  Udusa 
  

   was 
  taken 
  in 
  Scotland, 
  and 
  in 
  1844, 
  1865, 
  and 
  1877 
  it 
  was 
  seen 
  in 
  Ire- 
  

   land. 
  Generally, 
  however, 
  the 
  Clouded 
  Yellow 
  is 
  confined 
  to 
  the 
  south- 
  

   east 
  coast 
  of 
  England, 
  where 
  I 
  am 
  not 
  sure 
  that 
  it 
  occurs 
  every 
  year. 
  

   Hyale 
  has 
  been 
  taken 
  in 
  Ireland, 
  but 
  it 
  seems 
  to 
  have 
  pushed 
  no 
  farther 
  

   north 
  than 
  Northumberland, 
  where 
  it 
  was 
  captured 
  in 
  1834. 
  

  

  In 
  conclusion, 
  it 
  may 
  be 
  asked, 
  "Can 
  any 
  one 
  say 
  when 
  the 
  locusts 
  

   will 
  again 
  leave 
  their 
  breeding 
  grounds 
  and 
  ravage 
  the 
  cultivated 
  land 
  ? 
  " 
  

   To 
  this 
  question 
  I 
  think 
  a 
  ready 
  answer 
  may 
  be 
  given. 
  ^'Towards 
  the 
  

   next 
  period 
  of 
  fewest 
  sun-spots 
  and 
  earthquake 
  prevalence, 
  which 
  will 
  

   occur, 
  it 
  may 
  be 
  four, 
  it 
  may 
  be 
  ten 
  years 
  hence." 
  Again, 
  it 
  may 
  be 
  

   asked, 
  ^'Tell 
  us 
  if 
  the 
  ordinance 
  of 
  the 
  sun-stars 
  in 
  their 
  courses 
  is 
  at 
  

   present 
  for 
  or 
  against 
  their 
  increase." 
  To 
  this 
  question 
  my 
  data 
  do 
  not 
  

   enable 
  me 
  to 
  directly 
  reply. 
  It 
  has 
  been 
  said 
  by 
  one 
  writer 
  that 
  the 
  

   locusts 
  multiplied 
  at 
  the 
  time 
  Europe 
  was 
  visited 
  by 
  the 
  black 
  death 
  

   (1333-1359), 
  the 
  sweating 
  sickness 
  (1551-1553), 
  and 
  the 
  plague 
  of 
  Barbary 
  

   (1799-1800), 
  which 
  severally 
  indicated 
  sun 
  periods 
  when 
  epidemics 
  spread 
  

   northward. 
  For, 
  taking 
  out 
  the 
  great 
  cycles 
  of 
  east 
  and 
  west 
  deviation 
  

   of 
  the 
  magnetic 
  compass 
  as 
  uniform 
  (1814 
  W. 
  — 
  1580 
  E.— 
  1346 
  W.),^^ 
  syn- 
  

  

  26Soc. 
  Ent. 
  de 
  Belgique. 
  An., 
  torn. 
  1-4. 
  

  

  27 
  Entomologist 
  lor 
  1872, 
  two 
  taken 
  in 
  the 
  little 
  island 
  of 
  Sark 
  in 
  1872, 
  but 
  this 
  is 
  perhaps 
  nothing 
  

   unusual 
  ; 
  in 
  1876 
  I 
  noticed 
  a 
  few 
  near 
  Calais. 
  

  

  28 
  Tables 
  showing 
  the 
  east 
  and 
  west 
  variation 
  of 
  the 
  magnetic 
  needle 
  are 
  given 
  by 
  Sir 
  David 
  Brewster 
  

   in 
  his 
  Treatise 
  on 
  Magnetism. 
  The 
  cycles 
  are 
  given 
  as 
  from 
  1580 
  maximum 
  east 
  deviation, 
  to 
  1815 
  

   maximum 
  west 
  deviation 
  at 
  London; 
  1580 
  maximum 
  east 
  deviation, 
  to 
  1814 
  maximum 
  west 
  deviation 
  

   at 
  Paris 
  ; 
  and 
  the 
  maximum 
  west 
  deviation 
  at 
  the 
  Cape 
  of 
  Good 
  Hope 
  is 
  stated 
  to 
  have 
  occurred 
  in 
  

   1791, 
  that 
  is, 
  thirteen 
  years 
  earlier. 
  He 
  adds: 
  "Professor 
  Hansteen 
  has 
  explained 
  these 
  progressive 
  

   changes 
  in 
  the 
  variation 
  of 
  the 
  needle 
  by 
  the 
  motion 
  of 
  the 
  four 
  magnetic 
  poles. 
  Taking 
  the 
  varia- 
  

   tions 
  at 
  Paris 
  for 
  the 
  northern 
  hemisphere, 
  he 
  remarks 
  that 
  in 
  1580 
  the 
  weak 
  N. 
  pole 
  in 
  Siberia 
  waa 
  

   about 
  40° 
  E. 
  of 
  Greenwich, 
  or 
  to 
  the 
  N. 
  of 
  the 
  White 
  Sea; 
  while 
  the 
  strong 
  American 
  pole 
  was 
  about 
  

  

  