﻿ACADEMY 
  OF 
  SCIENCES. 
  383 
  

  

  backwards 
  into 
  the 
  hole 
  as 
  he 
  possibly 
  can 
  the 
  instant 
  he 
  perceives 
  that 
  you 
  

   have 
  caught 
  sight 
  of 
  him. 
  He 
  is 
  perfectly 
  ready 
  to 
  do 
  battle 
  with 
  another 
  of 
  

   his 
  species 
  who 
  may 
  endeavor 
  to 
  trespass 
  upon 
  his 
  cool 
  cavern, 
  and 
  will 
  pursue 
  

   the 
  trespasser 
  to 
  the 
  limits 
  of 
  his 
  premises. 
  

  

  If 
  you 
  turn 
  over 
  any 
  of 
  the 
  large 
  stones 
  which 
  cover 
  the 
  beach 
  at 
  Black 
  Point, 
  

   and 
  similar 
  localities, 
  you 
  are 
  sure 
  to 
  disturb 
  one 
  or 
  more 
  of 
  the 
  pretty 
  little 
  

   crabs 
  belonging 
  to 
  the 
  genus 
  Pseudograpsus. 
  Sometimes 
  as 
  many 
  as 
  twenty, 
  

   of 
  all 
  sizes, 
  from 
  half 
  an 
  inch 
  or 
  under 
  to 
  nearly 
  two 
  inches 
  in 
  width 
  of 
  carapax, 
  

   will 
  scuttle 
  away 
  from 
  under 
  a 
  single 
  stone. 
  There 
  are 
  two 
  species, 
  but 
  they 
  

   live 
  together 
  in 
  harmony, 
  as 
  becomes 
  relatives. 
  One 
  species, 
  the 
  Oregonensis, 
  

   is 
  of 
  a 
  bluish-gray 
  tint, 
  and 
  has 
  a 
  thin 
  covering 
  of 
  hairs 
  upon 
  its 
  hinder 
  legs. 
  

   ■J'he 
  other, 
  the 
  nudus, 
  is 
  one 
  of 
  the 
  prettiest 
  crabs 
  in 
  existence. 
  Its 
  large 
  pin- 
  

   cers 
  are 
  marbled 
  with 
  dark 
  purple 
  spots 
  on 
  a 
  lighter 
  ground 
  ; 
  the 
  legs 
  are 
  of 
  

   glossy 
  smoothness, 
  and 
  the 
  carapax 
  of 
  a 
  dark 
  purplish 
  red. 
  

  

  Several 
  species 
  of 
  hermit 
  crabs 
  — 
  little 
  crabs 
  with 
  a 
  soft 
  abdomen, 
  which 
  

   they 
  protect 
  by 
  ensconcing 
  it 
  in 
  the 
  shell 
  of 
  a 
  defunct 
  mollusk 
  — 
  are 
  found 
  in 
  

   and 
  near 
  San 
  Francisco. 
  Each 
  individual 
  chooses 
  a 
  shell 
  to 
  his 
  fancy, 
  and 
  

   abandons 
  it 
  for 
  a 
  larger 
  as 
  his 
  bulk 
  increases. 
  

  

  There 
  are 
  several 
  genera 
  — 
  those 
  with 
  the 
  right 
  hand 
  largest, 
  and 
  the 
  fingers 
  

   or 
  pincers 
  pointed 
  and 
  calcareous, 
  from 
  the 
  genus 
  Eupagurus 
  ; 
  those 
  with 
  

   spoon-shaped 
  fingers, 
  having 
  horny 
  tips, 
  and 
  the 
  left 
  hand 
  usually 
  largest, 
  are 
  

   known 
  as 
  Paguri 
  ; 
  while 
  others, 
  which 
  agree 
  with 
  the 
  last 
  in 
  having 
  spoon- 
  

   shaped, 
  horny 
  fingers, 
  but 
  have 
  hands 
  of 
  nearly 
  equal 
  size, 
  and 
  fingers 
  opening 
  

   horizontally, 
  form 
  the 
  genus 
  Clibanarius. 
  

  

  Another 
  curious 
  little 
  crab, 
  with 
  a 
  long, 
  narrow 
  body, 
  and 
  a 
  pointed 
  abdo- 
  

   men 
  folded 
  beneath 
  it, 
  is 
  not 
  found 
  alive 
  between 
  tide-marks, 
  but 
  its 
  body 
  is 
  

   often 
  washed 
  up 
  by 
  the 
  tide 
  on 
  the 
  sandy 
  beaches 
  just 
  outside 
  the 
  bay. 
  I 
  have 
  

   said 
  its 
  body, 
  but 
  it 
  would 
  be 
  more 
  correct 
  to 
  say 
  its 
  shell, 
  since 
  the 
  body 
  has 
  

   usually 
  been 
  eaten 
  clean 
  up 
  by 
  a 
  legion 
  of 
  sand-hoppers, 
  which 
  jump 
  out 
  of 
  the 
  

   shell 
  in 
  all 
  directions 
  when 
  you 
  pick 
  it 
  up. 
  The 
  name 
  is 
  Hippa 
  analoga. 
  

  

  Another 
  little 
  crustacean 
  bears 
  the 
  name 
  of 
  Porcellana 
  rupicola, 
  the 
  rock-in- 
  

   habiting 
  porcelain 
  crab. 
  It 
  dwells 
  under 
  rocks, 
  in 
  company 
  with 
  the 
  Pseudo- 
  

   grapsi, 
  and 
  is 
  abundant 
  at 
  Black 
  Point. 
  The 
  antennae 
  are 
  very 
  long, 
  and 
  

   folded 
  backwards 
  ; 
  the 
  carapax 
  is 
  almost 
  circular 
  and 
  flat 
  ; 
  the 
  hands 
  are 
  long, 
  

   broad, 
  and 
  flat, 
  and 
  the 
  fifth 
  or 
  hindermost 
  pair 
  of 
  legs 
  are 
  very 
  small, 
  and 
  

   olded 
  up 
  over 
  the 
  shell. 
  

  

  Two 
  other 
  species 
  of 
  Porcellana, 
  one 
  of 
  them 
  new 
  to 
  the 
  Pacific 
  Coast, 
  were 
  

   found 
  at 
  Mazatlan 
  by 
  Mr. 
  Edwards. 
  

  

  The 
  hermit 
  crabs, 
  porcelain 
  crabs, 
  and 
  the 
  long, 
  narrow 
  Hippa, 
  unlike 
  as 
  

   they 
  appear, 
  belong 
  to 
  the 
  same 
  tribe 
  of 
  the 
  ten-legged 
  crustaceans, 
  viz 
  : 
  the 
  

   Aaomoura, 
  so 
  called 
  from 
  the 
  usually 
  anomalous 
  condition 
  of 
  the 
  abdomen, 
  

   which 
  is 
  seldom 
  short 
  and 
  folded 
  under 
  the 
  thorax, 
  as 
  in 
  the 
  Brachyura, 
  or 
  true 
  

   crabs, 
  nor 
  yet 
  long 
  and 
  fully 
  provided 
  with 
  appendages, 
  as 
  in 
  the 
  lobster. 
  

  

  Another 
  singular 
  family, 
  belonging 
  to 
  this 
  tribe, 
  is 
  that 
  of 
  the 
  stone-crabs, 
  or 
  

   Litlwdia. 
  In 
  this 
  family 
  the 
  fifth 
  pair 
  of 
  feet 
  are 
  apparently 
  wanting, 
  but 
  are 
  

  

  