﻿158 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  vol. 
  103 
  

  

  the 
  family 
  Pythidae. 
  In 
  addition, 
  Mycterus 
  and 
  Cephaloon 
  both 
  

   have 
  prominent 
  procoxae 
  and 
  mesocoxae 
  and 
  the 
  prothorax 
  is 
  with- 
  

   out 
  lateral 
  margins. 
  Most 
  workers 
  in 
  the 
  past 
  have 
  considered 
  the 
  

   Oedemeridae 
  and 
  Cephaloidae 
  closely 
  allied, 
  but 
  my 
  incomplete 
  

   studies 
  of 
  the 
  male 
  genitalia 
  of 
  the 
  heteromerous 
  beetles 
  indicate 
  that 
  

   this 
  is 
  not 
  so. 
  The 
  very 
  different 
  structure 
  of 
  the 
  apical 
  abdominal 
  

   segments 
  of 
  the 
  species 
  of 
  Cephaloon 
  leads 
  me 
  to 
  suppose 
  that 
  these 
  

   species 
  are 
  far 
  removed 
  from 
  the 
  oedemerids, 
  but 
  their 
  true 
  affinities 
  

   are 
  not 
  yet 
  recognized. 
  

  

  Notes 
  on 
  the 
  distribution 
  oj 
  the 
  species. 
  — 
  As 
  can 
  be 
  seen 
  from 
  the 
  

   accompanying 
  map 
  (fig. 
  20), 
  the 
  species 
  of 
  this 
  family 
  show 
  the 
  typical 
  

   distribution 
  pattern 
  of 
  a 
  Holarctic 
  group 
  which 
  was 
  probably 
  derived 
  

   from 
  some 
  Asian 
  stock 
  and 
  spread 
  to 
  North 
  America 
  via 
  the 
  Alaskan 
  

   land 
  bridge. 
  It 
  is 
  interesting 
  to 
  note 
  that, 
  based 
  on 
  both 
  external 
  

   morphology 
  and 
  the 
  morphology 
  of 
  the 
  male 
  genitalia 
  (in 
  the 
  case 
  

   of 
  C. 
  pollens) 
  both 
  of 
  the 
  Asian 
  species 
  are 
  most 
  similar 
  to 
  two 
  of 
  the 
  

   Eastern 
  North 
  American 
  species 
  and 
  not 
  to 
  the 
  Western 
  North 
  

   American 
  species. 
  If 
  these 
  similarities 
  of 
  morphology 
  reflect 
  relation- 
  

   ship, 
  as 
  wo 
  assume 
  they 
  do, 
  then 
  we 
  again 
  see 
  the 
  often-repeated 
  

   pattern 
  of 
  a 
  pre-glacial 
  distribution 
  across 
  northern 
  Canada 
  from 
  

   Alaska, 
  down 
  through 
  Ontario 
  and 
  into 
  Eastern 
  United 
  States. 
  

   This 
  I 
  believe 
  to 
  be 
  a 
  further 
  stock-piling 
  of 
  evidence 
  against 
  the 
  

   theories 
  of 
  continental 
  drift 
  and 
  the 
  North 
  Atlantic 
  land 
  bridge 
  idea. 
  

  

  Genus 
  Cephaloon 
  Newman 
  

  

  Ichnodes 
  Dejean, 
  1834, 
  Cat. 
  Col. 
  ed. 
  3, 
  p. 
  227. 
  {Nomen 
  nudum, 
  one 
  ms. 
  trivial 
  

   name 
  listed.) 
  

  

  Cephaloon 
  Newman, 
  Ent. 
  Mag., 
  vol. 
  4, 
  p. 
  376, 
  1838. 
  (Genotype, 
  Cephaloon 
  

   lepturides 
  Newman; 
  1838; 
  monobasic.) 
  

  

  Cephalaon 
  Motschulsky 
  in 
  Schrenck, 
  Reisen 
  und 
  Forschungen 
  in 
  Amurlande, 
  

   vol. 
  2, 
  pt. 
  2, 
  p. 
  140, 
  I860. 
  (Error 
  for 
  Cephaloon.) 
  

  

  Typitium 
  Casey, 
  Ent. 
  News, 
  vol. 
  9, 
  p. 
  193, 
  1898. 
  (Genotype, 
  Cephaloon 
  ungulate 
  

   LeConte, 
  Proc. 
  Boston 
  Soc. 
  Nat. 
  Hist., 
  vol. 
  16, 
  p. 
  275, 
  1873; 
  original 
  desig- 
  

   nation 
  and 
  monobasic. 
  Placed 
  in 
  synonymy 
  by 
  Hopping 
  and 
  Hopping, 
  

   Pan-Pacific 
  Ent., 
  vol. 
  10, 
  p. 
  64, 
  1934.) 
  

  

  Sponidium 
  Casey, 
  Ent. 
  News, 
  vol. 
  8, 
  p. 
  193, 
  1898. 
  (Genotype, 
  Cephaloon 
  

   tenuicorne 
  LeConte, 
  1873; 
  present 
  designation. 
  Placed 
  in 
  synonymy 
  by 
  

   Hopping 
  and 
  Hopping, 
  1934.) 
  

  

  Ephamillus 
  Semenow, 
  Horae 
  Soc. 
  Ent. 
  Ross., 
  vol. 
  34, 
  p. 
  495, 
  1900. 
  (New 
  

   synonymy. 
  Genotype, 
  Cephaloon 
  variabile 
  Semenow 
  «= 
  Cephaloon 
  variabilis 
  

   Motschulsky 
  in 
  Schrenk, 
  1860; 
  original 
  designation 
  and 
  monobasic.) 
  

  

  Drachylis 
  Casey, 
  1898, 
  Ent. 
  News, 
  vol. 
  9, 
  p. 
  195. 
  (New 
  synonymy. 
  Genotype, 
  

   Drachylis 
  simulans 
  Casey, 
  1898; 
  monobasic.) 
  

  

  Discussion. 
  — 
  The 
  type 
  and 
  only 
  known 
  specimen 
  of 
  Drachylis 
  

   simulans 
  Casey, 
  the 
  genotype 
  of 
  Drachylis 
  Casey, 
  has 
  been 
  examined. 
  

   This 
  is 
  an 
  unfortunate 
  example 
  of 
  the 
  description 
  of 
  a 
  species 
  on 
  one 
  

  

  