2^3 
waste  any  time,  bill  proceeds  to  fdl  itself  voraciously  almosl  as  soon 
as  it  has  settled.  So  far  as  our  experience  goes,  GL  morsUans  is 
much  the  more  troublesome. 
Oil  tlio  march,  wherever  67.  morsHans  was  at  all  plentiful,  all  the  carriers 
pruvitlecl  Ihemselveg  with  hunches  of  leaves,  ami  the  comstant  souml  of  these 
siriliing  the  shin  bore  evidence  to  the  viciousness  of  the  Hies. 
Ill  most  places  the  conditions  under  which  we  caught  Gl.  palpalis, 
a|iproach  closely  to  those  obtaining  in  ITganda  and  other  parts  of 
Africa;  that  is,  there  was  fairly  abundant  shade  afforded  liy  the  trees 
and  bushes  along  the  water  courses,  but  on  Lake  Tanganyika  a  most 
slriking  difference  was  noticed.  This  lake  is  closed  in  by  iirecipitoiis 
cliffs  from  one  to  two  thousand  feet  high,  wliich  come  to  wilhin  a 
short  distance  of  the  water.  The  shores  shelve  gradually  from  Ihe  foot 
of  the  hills,  are  sandy  or  pebbly,  and  are  either  quite  devoid  of 
vegetation,  or,  at  most,  furnished  witli  small  patches  of  the  reed  known 
locally  as  ‘mtete’  or  ‘  bango  ’  {Phragmkes  conitiiiinis).  In  only  a 
very  few  places  does  this  assume  any  luxuriance  of  growth,  yet  it  was 
noted  that  the  fly  could  almost  always  be  found  at  even  the  scantiest 
collection  of  isolated  rceils.  'Phey  were  frequently  seen  liasking  in 
Ihe  sun,  on  the  rocks  at  the  water's  edge.  The  whole  picture 
presented  by  these  rocky  beaches  with  small,  .scattered  patches  of 
reeds  differs  very  materially  Irom  what  has  been  considered  to  he 
typical  '  pal  Palis'  country,  i.e.,  wooded  banks  affording  plentiful 
sliade.  This  may  be  a  local  peculiarity  of  the  species  {Glossina 
pnlpalis,  Rob.-JDesv.,  var.  ivcllviani,  Austen,  and  intermediate  forms 
between  this  and  the  type  species),  or  it  may  indicate  that  in  the 
absence  of  more  tavourable  conditions,  other  factors  being 
suitable,  the  fly  is  capable  of  a  certain  amount  of  adaptability,  and 
this,  of  course,  becomes  of  some  importance  in  consirlering  the 
possible  extension  of  the  species.  We  have  been  informed  lay 
Prof.  Podd  that  Gl.  pnlpalis  is  common  on  long  stretches  of  the 
Upper  C  ongo,  where  the  banks  on  either  side  are  covered  with  grass 
alone. 
On  the  Lovii  river,  along  the  portion  examined  by  us,  (he  banks 
are  covered  with  a  dense  growth  of  the  reed  we  have  mentioned 
above,  and  onl}/-  an  odd  bush  or  two,  yet  the  fly  was  very  abundant. 
The  shade  afforded  by  the  reeds  was,  however,  very  dee])  here. 
Many  observers  have  noted  a  seasonal  variation  in  the  niimlier  of 
