NO.    5      MALE  GEMTALIA  OF  ORTHOPTEROID  INSECTS — SNODGRASS        97 
spermatophoric  insemination.  Structurally,  the  acridid  phallus  be- 
longs to  the  tettigonioid  type,  in  so  far  as  the  primary  phallomeres 
unite  to  form  a  single  organ ;  but  any  closer  relationship  to  either  the 
tettigoniid  or  gryllid  form  is  not  clear,  either  from  the  adult  structure 
or  the  nymphal  development. 
The  mating  and  copulating  habits  of  the  grasshoppers  are  well 
known,  but  only  a  few  studies  have  been  made  on  the  manner  of  sperm 
transfer.  According  to  the  accounts  of  different  investigators  it  would 
appear  that  some  species  produce  a  number  of  small  spermatophores 
and  eject  them  entirely  into  the  sperm  receptacle  of  the  female,  while 
others  insert  only  the  end  of  a  long  neck  from  a  single  bulblike 
spermatophore  into  the  receptaculum  (see  Snodgrass,  1935,  pp.  71-73)- 
Fedorov  (1927)  claims  that  the  first  type  of  insemination  occurs  with 
Anacridhim  aegyptiuin  ;  Boldyrev  (1929)  describes  the  second  for 
Locusfa  imgratoria,  the  spermatozoa  in  this  case  being  pumped 
through  the  neck  of  the  spermatophore  into. the  receptaculum  of  the 
female  by  the  endophallic  apparatus  of  the  male,  after  which  the  end 
of  the  spermatophore  neck  breaks  off  and  remains  in  the  sperm 
receptacle.  The  structure  and  mechanism  of  the  phallic  organ  are  so 
nearly  the  same  in  all  species  of  Acrididae  that  we  should  scarcely 
expect  to  find  any  considerable  difference  in  the  manner  of  insemina- 
tion :  the  apparatus  appears  to  be  well  adapted  to  the  type  of  action 
described  by  Boldyrev. 
The  acridid  phallus  consists  of  a  complex  ectophallus  contained  in 
the  genital  chamber  (fig.  41  A,  GC),  and  of  a  large,  strongly  muscu- 
lated,  bulblike  endophallus  (Enph)  projecting  downward  and  forward 
into  the  body  cavity  beneath  the  floor  of  the  genital  chamber.  The 
ejaculatory  duct  (Dej)  ends  in  a  muscularly  compressible  ejaculatory 
sac  (ejs)  that  opens  into  the  ventral  wall  of  the  endophallic  cavity 
between  two  sclerites  (y)  that,  operated  by  muscles  of  the  endophallic 
wall,  regulate  the  gono^Dore. 
The  ectophallus  includes  a  proximal  part,  or  phallobase  (fig.  41  A), 
and  a  diversified  distal  part,  which  may  be  termed  the  aedeagus  (Aed). 
The  phallobase  appears  as  a  membranous  elevation  of  the  floor  of  the 
genital  chamber,  having  its  distal  margin  produced  into  a  broad  basal 
fold  (bf)  overlapping  the  base  of  the  aedeagus ;  on  its  anterior  part  is 
situated  a  large,  irregular  sclerite,  the  epiphallus  (figs.  41  A,  42  I, 
Epph).  Between  the  basal  fold  and  the  epiphallus  there  may  be  a  deep 
depression  (fig.  42  I,  c).  The  aedeagus  (fig.  41  A,  Aed)  is  differen- 
tiated into  several  parts,  but  its  major  subdivision  is  into  a  dorsal 
lobe  {dl)  and  a  ventral  lobe  (vl),  between  which  is  the  phallotreme, 
or  opening  from  the  endophallic  cavity.    The  dorsal   lobe   itself   is 
