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SMITHSONIAN    MISCELLANEOUS    COLLECTIONS  VOL,    96 
The  seminal  vesicles.- — ^The  presence  of  special  vesicles  for  the 
storage  of  the  spermatozoa  appears  to  have  been  overlooked  by  other 
students  of  the  reproductive  organs  of  the  roaches.  Ito  (1924)  states 
there  are  no  seminal  vesicles  in  Blatta  oricntalis,  and  that  the  sperm 
is  stored  in  the  anterior  enlarged  part  of  the  ejaculatory  duct.  Miall 
and  Denny,  as  above  noted,  believed  that  the  accessory  gland  tubules 
Eppt      XT 
rPhm 
Fig.  12. — Blattoidea:  adult  and  immature  structure  of  the  male  abdomen,  and 
nymphal  genitalia  of  Blatta  oricntalis  Linnaeus. 
A,  end  of  abdomen  of  adult  male,  dorsal  view.  B,  same,  ventral  view.  C,  same, 
posterior  view.  D,  nymph  11  mm  long,  ventral  surface  of  abdomen.  E,  same, 
genital  chamber  exposed  from  above,  showing  three  simple  phallomeres  aris- 
ing from  anterior  wall  around  gonopore.  F,  nymph  22  mm  long,  showing 
later  stage  of  phallomeres,  and  mesodermal  ampullae  united  with  anterior 
end  of  ectodermal  ejaculatory  duct. 
Amp,  mesodermal  ampulla  of  ejaculatory  duct;  Cer,  cercus;  Dej,  ductus 
ejaculatorius ;  Eppt.  epiproct ;  GC,  genital  chamber;  IP  Inn,  left  phallomere ; 
Papt,  paraproct ;  rPhm,  right  phallomere ;  Sty,  stylus ;  Vd,  vas  deferens ;  vPhni, 
ventral  phallomere;  x-x,  cut  wall  of  genital  chamber. 
are  filled  with  spermatozoa.  How^ever,  in  Blatta,  Periplancta,  and 
Blattella,  at  least,  there  are  special  sperm-containing  vesicles  arising 
from  the  anterior  end  of  the  ejaculatory  duct  among  the  gland  tubules. 
The  seminal  vesicles  of  Blattella  are  tw^o  small  oval  sacs  arising  close 
together  from  the  end  of  the  right  branch  of  the  ejaculatory  duct 
(fig.  16  C,  Vsm),  where  ordinarily  they  are  concealed  by  the  accessory 
gland  tubules.  They  are  filled  with  spermatozoa,  and  are  similar  to  the 
sperm  vesicles  of  the  mantid  Tenodera  (fig.  9B)  except  that  both 
