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SMITHSONIAN    MISCELLANEOUS    COLLECTIONS  VOL.    96 
evidently  passed  the  functional  stage,  for  the  testes  consisted  of 
long,  delicate,  threadlike  tubes  having  no  evident  cellular  structure. 
The  long  tubular  testis  of  Leptyniella  (fig.  7  A),  according  to 
De  Sinety  (1901 ),  consists  of  a  mass  of  cysts,  containing  spermatozoa 
in  different  stages  of  development,  enclosed  in  a  cellular  envelope. 
Fig.  7. — Phasmatoidea :   male  and  female  genitalia. 
A,  Leptyniella  attemiata  (Pantel),  male  internal  reproductive  organs  (com- 
bined from  De  Sinety,  1901).  B,  Tiniema  ealifornica  Scudder,  male,  internal 
reproductive  organs.  C,  Diapheromcra  femora  fa  (Say),  male,  internal  repro- 
ductive organs  except  testes.  D,  same,  female,  base  of  ovipositor  and  dorsal 
wall  of  genital  chamber  with  spermathecal  opening.  E,  same,  spermathecae  and 
ducts.    F,  same,  single  spermatheca  and  duct,  optical  section. 
AcGlds,  accessory  glands;  Dcj,  ductus  ejaculatorius ;  Dct,  duct  of  sper- 
matheca ;  Spy,  spermathecal  aperture ;  Spt,  spermatheca ;  Tes,  testes ;  Vd,  vas 
deferens ;  iVl,  3VI,  first  and  third  valvulae  of  ovipositor ;  Vsm,  vesicula  semi- 
nalis ;  x,  cut  edge  of  genital  chamber  wall. 
The  spermatogonia!  cysts  lie  along  the  dorsal  crest  of  the  testis,  which 
presents  a  series  of  low  elevations,  while  the  cysts  containing  ma- 
ture spermatozoa  occupy  the  ventral  part  of  the  organ,  which  is 
traversed  by  the  vas  deferens.  The  testes  of  Carausius  are  said  by 
Pehani  (1925)  to  have  the  same  structure  as  that  described  by 
De  Sinety  for  Leptyniella.  The  simple  tubular  form  of  phasmatid 
testis  might  be  supposed  to  represent  a  primitive  gonadial  structure 
