﻿308 
  REV. 
  R. 
  BARON 
  ON 
  THE 
  

  

  portions 
  of 
  the 
  rock 
  the 
  fossils 
  of 
  leaves 
  were 
  exceedingly 
  numerous, 
  

   one 
  of 
  which 
  I 
  recognized 
  as 
  that 
  of 
  Galophyllumparviflorum, 
  Bojer 
  ; 
  

   and 
  another, 
  judging 
  from 
  its 
  veining, 
  seemingly 
  belonged 
  to 
  the 
  

   Natural 
  Order 
  XLelastomaceae, 
  and 
  not 
  improbably 
  to 
  the 
  genus 
  Medi- 
  

   nilla. 
  These 
  had 
  been 
  washed 
  down 
  into 
  the 
  lake 
  from 
  the 
  forest 
  

   on 
  the 
  western 
  hill-range, 
  where 
  to 
  this 
  day 
  the 
  former 
  plant, 
  as 
  

   well 
  as 
  various 
  species 
  of 
  Medinilla, 
  are 
  still 
  found. 
  

  

  It 
  remains 
  only 
  to 
  add 
  with 
  regard 
  to 
  this 
  old 
  lake-bed 
  that 
  it 
  

   has 
  been 
  considerably 
  worn 
  by 
  various 
  rivers 
  and 
  streams, 
  notably 
  

   the 
  ILangoro 
  in 
  Ankay, 
  and 
  the 
  Mandremoka 
  in 
  east 
  Androna, 
  into 
  

   a 
  system 
  of 
  hills 
  and 
  valleys, 
  many 
  of 
  the 
  latter 
  being 
  now 
  well 
  

   wooded, 
  so 
  that 
  its 
  original 
  features 
  have 
  become, 
  in 
  many 
  places, 
  

   so 
  effaced 
  as 
  to 
  be 
  almost 
  unrecognizable. 
  

  

  At 
  Antsirabe, 
  about 
  40 
  miles 
  south 
  of 
  the 
  capital, 
  there 
  is 
  the 
  

   dried-up 
  bed 
  of 
  another 
  ancient 
  lake, 
  but 
  of 
  much 
  smaller 
  dimen- 
  

   sions 
  than 
  the 
  one 
  described 
  above. 
  As 
  there 
  are 
  extinct 
  volcanoes 
  

   near, 
  this 
  ancient 
  lake 
  may 
  not 
  improbably 
  have 
  owed 
  its 
  existence 
  to 
  

   former 
  volcanic 
  action. 
  It 
  was 
  in 
  the 
  bed 
  of 
  this 
  ancient 
  lake 
  that 
  

   Dr. 
  Hildebrandt 
  a 
  few 
  years 
  ago 
  discovered 
  the 
  semifossilized 
  bones 
  

   of 
  a 
  Hippopotamus, 
  which 
  is 
  now 
  extinct 
  in 
  Madagascar, 
  but 
  which 
  

   was 
  probably 
  in 
  existence 
  at 
  no 
  very 
  remote 
  period, 
  since 
  there 
  is 
  

   still 
  a 
  native 
  name 
  for 
  the 
  animal 
  (Lalomena). 
  Whether 
  this 
  is 
  

   the 
  same 
  species 
  of 
  Hippopotamus 
  {H. 
  Lemerlei) 
  as 
  that 
  found 
  by 
  

   M. 
  Grandidier 
  in 
  the 
  south-west 
  of 
  the 
  island, 
  I 
  cannot 
  say, 
  but 
  

   not 
  improbably 
  it 
  is. 
  In 
  some 
  places, 
  where 
  the 
  streams 
  have 
  

   excavated 
  the 
  dried-up 
  bed 
  of 
  this 
  ancient 
  lake, 
  there 
  may 
  be 
  seen 
  

   layers 
  of 
  lapilli 
  and 
  volcanic 
  sand. 
  

  

  Crystalline 
  Schists, 
  &c. 
  

  

  I 
  have 
  said 
  above 
  that 
  the 
  dominant 
  strike 
  of 
  the 
  crystalline 
  rocks 
  

   is 
  about 
  15° 
  to 
  the 
  east 
  of 
  north 
  ; 
  but 
  we 
  naturally 
  expect 
  to 
  meet 
  

   with 
  local 
  variations 
  in 
  a 
  country 
  which 
  has 
  been 
  subject 
  to 
  such 
  vast 
  

   disturbances 
  as 
  Madagascar, 
  and 
  these 
  we 
  find. 
  For 
  instance, 
  a 
  few 
  

   miles 
  north 
  and 
  north-west 
  of 
  Antananarivo, 
  the 
  strike 
  and 
  direction 
  

   of 
  the 
  hill-ranges 
  (Andringitra, 
  Ampananina, 
  &c.) 
  is 
  mainly 
  east 
  and 
  

   west, 
  with 
  the 
  dip 
  towards 
  the 
  north 
  at 
  an 
  angle 
  of 
  about 
  35° 
  or 
  40°. 
  

   These 
  ranges 
  apparently 
  commence 
  somewhere 
  in 
  the 
  neighbourhood 
  

   of 
  Ambohimanga, 
  and 
  run 
  west 
  for 
  a 
  distance 
  of 
  60 
  or 
  80 
  miles. 
  

   In 
  one 
  part 
  of 
  their 
  course 
  the 
  strata 
  become 
  vertical 
  or 
  nearly 
  so; 
  

   this 
  occurs 
  a 
  little 
  to 
  the 
  north-west 
  of 
  Ambohibeloma, 
  where 
  there 
  

   is 
  a 
  sharp 
  ridge 
  or 
  series 
  of 
  ridges, 
  the 
  highest 
  of 
  which 
  forms 
  the 
  

   mountain 
  of 
  Ambohitrondrana, 
  30 
  or 
  40 
  miles 
  W.N.W. 
  of 
  Antana- 
  

   narivo. 
  

  

  In 
  some 
  localities 
  these 
  ridges 
  of 
  gneiss, 
  in 
  consequence 
  often 
  of 
  

   the 
  tilting 
  of 
  the 
  strata 
  at 
  a 
  high 
  angle, 
  present 
  remarkably 
  jagged 
  

   and 
  serrated 
  outlines, 
  and 
  are 
  striking 
  in 
  their 
  grandeur. 
  This 
  is 
  

   specially 
  true 
  of 
  the 
  mountain 
  of 
  Vavavato, 
  about 
  60 
  miles 
  to 
  the 
  

   south-west 
  of 
  Antananarivo. 
  

  

  