560 
Round  forms.  Frequently,  especially  in  lice  taken  from  rats  at 
a  later  stage  of  infection,  round  forms,  as  m  Figs.  32-36,  were  noted. 
'I'hey  usually  showed  a  typical  oblong  nucleus  and  a  small  blepharo- 
plast,  from  which  a  long,  round  flagellum,  which  was  usually  wound 
round  the  parasite,  originated.  Whether  these  forms  develop  in  the 
way  suggested  by  Fig.  31,  or  whether  they  result  from  the  coiling  up 
of  a  normal  trypanosome  could  not  be  determined. 
LITERATURE 
1.  Prijwazius'..  Siudien  iiber  Saugethier  Trypanosoinen.  Arb.  a.  d.  kaisl.  Gesuiul- 
heitsamte.  Bd.  XXII,  Heft  2. 
2.  P.vrroN  Axn  Stricklanu.  A  critical  re\ie\v  of  tiie  Relation  of  Blood-sucking 
Invertebrates  to  the  Life  Cycles  of  the  Trypanosomes  of  A'Trtebrates,  etc. 
Parasitology,  Vol.  I,  No.  4,  1908. 
3.  Ncttall,  G.  The  Transmission  of  Trypanosoma  lesvisi  by  Fleas  and  Lice. 
Parasitology,  Vol.  I,  No.  4,  1908. 
B.vldrv.  Versuche  und  Beobachtung  iiber  die  Entwickelung  von  Trypanosoma 
Icu'isi  in  der  Rattenlaus,  Haematopinus  spinulostis.  Arch,  f  Protistenknnde. 
Bd.  XV,  1909. 
5.  .Muork  and  Brkini,.  The  Cytology  of  Trypanosomes,  Part  1.  Annals  of  Tropical 
.Medicine  and  Parasitology,  Vol.  I,  1907. 
