402 
Fig.  16.  Platyrhachus  flavistemus,  keel  of  the  16th  segment. 
»  16a.  »               »          left  copulatory  foot,  external  view. 
»  166.  »             '  »           right  copulatory  foot,  from  below. 
»  17.  »        subalbus,  keel  of  16th  segment. 
»  17a.  »            »       left  copulatory  foot  from  below. 
»  176.  »            »          ditto  inside. 
»  18.  »        xanthopus,  keel  of  the  7th  segment. 
»  18a.  »             »        right  copulatory  foot  from  outside. 
»  19.  »        subspinosus,  ditto  from  below. 
»  19a.  »              »          keel  of  16th  segment. 
»  20.  »        verrucosus,  right  copulatory  foot  from  below. 
»  20a.  »             »          ditto  from  the  side. 
»  206.  »             »          keel  of  7th  segment. 
PLATE  XX. 
Fig.    1.  Sphaeropoeus  hercules,  nat.  size. 
»       la.  »  »       extremity  of  posterior  copulatory  foot. 
»       lb.  »  »  ditto. 
»       lc.  »  »       vulva  of  Q. 
»       2.  Zephronia  nigriceps ,  nat.  size. 
»       2a.  »  »       copulatory  apparatus  from  before. 
»       2b.  »  »       vulva  of  Q. 
»       3.  Siphonorhinus  pallipes ,  lateral  view  X  t- 
»       3a.  »  »       lateral  view  of  anterior  end. 
»       4.  Siphonophora  vittata,  dorsal  view. 
»       4a.  »  »       upper  view  of  head. 
»       5.  Siphonotus  formosus,  dorsal  view  enlarged. 
»       5a.  »  »        anterior  end,  from  the  side. 
»       6.  Siphonocryptus  compactus,  dorsal  view. 
»       6a.  »  »        dorsal  view  of  anterior  end. 
»       6b.  »  »         ventral  view  of  anterior  end. 
»       6c.  »  »        dorsal  view  of  posterior  end. 
»       7.  Platyrhachus  mirandus ,  nat.  size  cf. 
»       7a.  »  »        right  copulatory  foot,  from  below. 
»       76.  »  »        ditto  from  outside. 
»       8.  »  laticollis,  nat.  size  Q. 
»       8a.  »  »        right  copulatory  foot  from  outside. 
»       86.  »  »        keel  of  7th  segment. 
»       9.  »  weberi,  nat.  size  cf. 
»       9a.  »   *  »       keel  of  7th  segment. 
»       96.  »  »       left  copulatory  foot  from  below. 
»       9c.  »  »       ditto  from  the  inside. 
»  10.  »         monticola,  nat.  size  Q. 
»  10a.  »              »         right  copulatory  foot  from  below. 
»  106.  »              »        keel  of  7th  segment. 
»  10c.  »              »        keel  of  16th  segment. 
PLATE  XXI. 
Fig.    1.    Platyrhachus  submissus ,  nat.  size  cf. 
»       la.  »  j>         left  copulatory  foot,  from  inside. 
