﻿ART. 
  'i'i 
  

  

  NEW 
  LAND 
  SHELLS 
  FROM 
  MEXICO 
  BARTSCH 
  

  

  rough 
  lines 
  of 
  growth. 
  Aperture 
  broadly 
  pear-shaped 
  with 
  the 
  outer 
  

   lip 
  decidedly 
  expanded, 
  thickened, 
  and 
  reflected 
  into 
  a 
  disjunct 
  

   peristome. 
  

  

  The 
  type, 
  Cat. 
  No. 
  361962, 
  U.S.N.M., 
  was 
  collected 
  at 
  southeast 
  

   Monclova, 
  Coahuila, 
  Mexico. 
  It 
  has 
  16.5 
  whorls 
  and 
  measures: 
  

   Length, 
  20.9 
  mm.; 
  diameter, 
  6.3 
  mm. 
  

  

  Cat. 
  No. 
  361963, 
  U.S.N. 
  M., 
  contains 
  24 
  additional 
  specimens 
  

   which 
  yield 
  the 
  following 
  measurements: 
  

  

  •Type. 
  

  

  HOLOSPIRA 
  (EUDISTEMMA) 
  PICTA, 
  new 
  species 
  

  

  Plate 
  1, 
  figs. 
  3, 
  4 
  

  

  Shell 
  acicular, 
  bluish-white, 
  with 
  a 
  narrow 
  zone 
  of 
  rusty-brown 
  

   immediately 
  below 
  the 
  summit. 
  The 
  area 
  immediately 
  behind 
  the 
  

   aperture 
  is 
  also 
  very 
  dark-brown, 
  the 
  basal 
  portion 
  being 
  a 
  little 
  paler. 
  

   Interior 
  of 
  aperture 
  brown. 
  Nuclear 
  whorls 
  2.2, 
  well 
  rounded, 
  with 
  

   an 
  indication 
  of 
  distantly 
  spaced 
  axial 
  lines 
  of 
  growth 
  which 
  hint 
  at 
  a 
  

   progressive 
  state 
  of 
  sculpture; 
  that 
  is, 
  the 
  postnuclear 
  sculpture 
  is 
  

   passing 
  up 
  on 
  the 
  nuclear 
  turns. 
  Postnuclear 
  whorls 
  narrow, 
  the 
  

   early 
  ones 
  well 
  rounded, 
  the 
  later 
  only 
  moderately 
  so, 
  all 
  appressed 
  

   at 
  the 
  summit. 
  The 
  first 
  four 
  are 
  marked 
  by 
  decidedly 
  retractively 
  

   curved, 
  slender 
  axial 
  riblets 
  which 
  are 
  about 
  one-third 
  as 
  broad 
  as 
  

   the 
  spaces 
  that 
  separate 
  them. 
  The 
  riblets 
  become 
  increasingly 
  

   less 
  developed 
  from 
  the 
  first 
  to 
  the 
  last 
  of 
  these 
  turns 
  after 
  which 
  

   they 
  become 
  quite 
  obsolete, 
  so 
  that 
  the 
  following 
  turns 
  are 
  marked 
  

   only 
  by 
  indications 
  of 
  lines 
  of 
  growth. 
  However, 
  on 
  the 
  last 
  two 
  

  

  