Vol.  49. J  VOLCANIC  ROCKS  PROM  THE  NEW  HEBRIDES. 
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same  species,  and  that  was  on  the  southern  side  of  Efate  in  the 
previous  year. 
A  short  distance  to  the  westward  of  Mai  Island  is  an  outlying 
reef  of  atoll-formation,  called  Cook  Beef.  The  outer  edge  shows 
dry  patches  at  low  water,  while  the  lagoon  has  a  general  depth  of 
about  6  feet,  with  numerous  scattered  coral-heads  almost  awash  at 
low  water. 
6.  The  Shepherd  Islands  form  a  group  extending  south-eastwards 
from  Epi.  They  are  all  of  volcanic  origin,  and  apparently  of  recent 
formation.  No  coral  was  found  growing  round  the  shores  of  any 
of  these  islands  or  on  the  adjacent  coast  of  Epi,  and  on  but  few 
occasions  was  any  coral  brought  up  on  the  lead. 
Native  tradition  states  that  a  great  earthquake  accompanied  by  a 
volcanic  eruption  took  place  some  250  or  300  years  ago,  when  these 
islands,  which  then  formed  part  of  Epi,  were  broken  up  into  their 
present  form.  Their  relative  position  and  appearance  add  weight 
to  the  report. 
7.  Near  the  north-eastern  point  ©f  Tongoa  Island ,  which  on  the 
above  supposition  would  be  on  the  south  side  of  the  crater,  is  a 
district  some  20  to  25  acres  in  extent,  where  the  ground  is  heated 
almost  to  water-boiling-point.  It  is  situated  close  to  the  coast,  upon 
a  cliff  rising  some  50  feet  above  the  sea.  There  is  little  vegetation 
over  this  area,  plant-growth  being  restricted  to  some  coarse  grass 
and  a  few  stunted  bushes.  But  in  the  immediate  vicinity,  vege¬ 
tation  is  luxuriant  in  the  extreme,  and  cocoanut  palms  were 
producing  ripe  fruit  when  only  2  or  3  years  old.  Steam  and 
other  vapours  rise  from  the  ground  at  several  different  spots,  espe¬ 
cially  in  the  hollows  of  the  surface.  Unfortunately,  no  thermometer 
was  available  for  testing  the  temperature,  but  in  several  places  the 
•exposed  surface  was  too  hot  for  the  palm  of  the  hand  to  rest  on 
for  more  than  a  second  or  two.  The  natives  take  advantage  of 
this  natural  oven  to  cook  their  food  in  holes  dug  for  the  purpose. 
8.  B allicolo  Island ,  known  as  Malehula  by  the  natives,  one  of 
the  largest  of  the  New  Hebrides,  has  both  coral  and  volcanic  for¬ 
mations. 
On  the  hills  overlooking  Port  Stanley,  on  the  north-eastern 
•coast  of  the  island,  coral-limestone  was  found  at  a  height  of  about 
500  feet  above  sea-level.  The  rock  is  described  in  Appendix  II.,  and 
no  doubt  may  be  found  in  other  parts  of  the  island. 
Appendix  I. 
Volcanic  Hocks  from  the  New  Hebrides. 
By  J.  J.  H.  Teall,  Esq.,  M.A.,  F.B.S.,  Sec.G.S. 
Tongoa  Island ,  from  the  4  hot  ground.’ — A  black  rock  with  resinous 
lustre,  containing  numerous  small,  glassy,  porphyritic  felspars. 
Microscopic  characters. — Plagioclase  and  augite  occur  as  porphy¬ 
ritic  constituents.  The  plagioclase  is  allied  to  labradorite,  and 
shows  the  usual  characters  of  that  mineral  as  it  occurs  in  the 
