﻿254 
  PROCEEDINGS 
  OF 
  THE 
  CALIFORNIA 
  

  

  On 
  New 
  Parasitic 
  Crustacea, 
  from 
  the 
  N. 
  W. 
  Coast 
  of 
  

   America. 
  * 
  

  

  BY 
  W. 
  H. 
  DALL, 
  U. 
  S. 
  COAST 
  SURVEY. 
  

  

  More 
  than 
  a 
  year 
  ago, 
  I 
  submitted 
  to 
  the 
  Academy 
  descriptions 
  of 
  three 
  new 
  

   species 
  of 
  Cyami, 
  from 
  as 
  many 
  species 
  of 
  Pacific 
  Cetacea. 
  Oh 
  examination 
  of 
  

   a 
  small 
  collection 
  of 
  parasites, 
  in 
  the 
  collection 
  of 
  the 
  Academy, 
  (presented 
  by 
  

   Captain 
  C. 
  M. 
  Scammon, 
  and 
  reported 
  to 
  have 
  been 
  procured 
  from 
  a 
  Pacific 
  

   Right 
  Whale, 
  near 
  the 
  Island 
  of 
  Kadiak, 
  Alaska, 
  in 
  1873) 
  I 
  find 
  that 
  it 
  con- 
  

   tains 
  two 
  species, 
  both 
  apparently 
  undescribed. 
  It 
  is 
  to 
  be 
  presumed 
  that 
  each 
  

   species 
  of 
  whale 
  has 
  parasites 
  peculiar 
  to 
  itself, 
  and 
  those 
  who 
  have 
  the 
  op- 
  

   portunity 
  of 
  collecting 
  these 
  interesting 
  animals 
  should 
  lose 
  no 
  opportunity 
  of 
  

   examining 
  the 
  rarer 
  cetacea, 
  and 
  should 
  preserve 
  the 
  parasites 
  of 
  each 
  species 
  

   carefully 
  by 
  themselves. 
  As 
  there 
  are 
  many 
  species 
  from 
  which 
  no 
  parasites 
  

   have 
  yet 
  been 
  collected, 
  there 
  are 
  doubtless 
  as 
  many 
  kinds 
  of 
  Cyami 
  which 
  are 
  

   still 
  unknown. 
  

  

  The 
  species 
  described 
  on 
  pp. 
  281-3, 
  Vol. 
  IV 
  of 
  the 
  Academy's 
  Proceedings, 
  

   have 
  been 
  well 
  figured 
  on 
  plate 
  X 
  of 
  Captain 
  Scammon's 
  Marine 
  Mammals 
  of 
  

   the 
  N. 
  W. 
  Coast 
  of 
  America, 
  and, 
  in 
  default 
  of 
  a 
  figure 
  of 
  the 
  present 
  species, 
  

   I 
  have 
  preferred 
  to 
  give 
  a 
  comparative 
  diagnosis, 
  by 
  which 
  they 
  may 
  be 
  more 
  

   readily 
  distinguished 
  from 
  the 
  figured 
  and 
  other 
  described 
  species. 
  

  

  Cyamus 
  tentator, 
  n. 
  s. 
  

  

  Species 
  in 
  size 
  and 
  general 
  form 
  resembling 
  C. 
  Scammoni 
  Dall, 
  (Scammon, 
  loc. 
  

   cit. 
  pi. 
  X, 
  figure 
  2) 
  of 
  a 
  pale, 
  waxy 
  yellow, 
  with 
  the 
  tips 
  of 
  the 
  branchiae 
  pur- 
  

   plish. 
  It 
  differs 
  from 
  C. 
  Scammoni 
  in 
  the 
  following 
  particulars 
  : 
  Head 
  pro- 
  

   portionately 
  smaller, 
  not 
  constricted 
  behind 
  the 
  eyes, 
  terminating 
  in 
  a 
  point 
  in 
  

   the 
  median 
  line 
  behind, 
  which 
  point 
  overlaps 
  a 
  median 
  channel 
  in 
  the 
  body 
  

   segment. 
  Second 
  pair 
  of 
  antennae 
  proportionately 
  much 
  longer, 
  equaling 
  

   twice 
  the 
  length 
  of 
  the 
  head. 
  Second 
  pair 
  of 
  hands, 
  with 
  two 
  sharp, 
  spike-like 
  

   tubercles 
  in 
  place 
  of 
  the 
  two 
  rather 
  short 
  and 
  blunt 
  tubercles 
  of 
  C. 
  Scammoni. 
  

   Hands 
  otherwise 
  very 
  similar. 
  Second 
  segment 
  with 
  a 
  broad 
  channel 
  iu 
  the 
  

   median 
  line, 
  widening 
  backward 
  from 
  the 
  head, 
  and 
  rather 
  shallow. 
  Third 
  

   segment 
  not 
  rounded 
  at 
  its 
  outer 
  ends, 
  but 
  furnished 
  with 
  very 
  prominent 
  knobs, 
  

   at 
  the 
  anterior 
  and 
  posterior 
  corners 
  on 
  each 
  side. 
  The 
  outer 
  edges 
  of 
  the 
  

   fourth 
  segment 
  are 
  also 
  knobbed 
  before 
  and 
  behind, 
  but 
  the 
  anterior 
  knobs 
  are 
  

   less 
  prominent. 
  The 
  branchiae 
  are 
  not 
  spirally 
  twisted, 
  but 
  are 
  straight, 
  

   laterally 
  extended 
  cylinders, 
  nearly 
  as 
  long 
  as 
  the 
  width 
  of 
  the 
  segment 
  to 
  which 
  

   they 
  are 
  attached. 
  There 
  are 
  two 
  pairs 
  on 
  each 
  side 
  of 
  the 
  third 
  and 
  fourth 
  

   segments 
  in 
  the 
  male. 
  The 
  upper 
  pair 
  on 
  each 
  side 
  are 
  not 
  of 
  equal 
  length, 
  as 
  

   in 
  C. 
  Scammoni, 
  but 
  the 
  inferior 
  branchia 
  of 
  this 
  pair 
  is 
  much 
  shorter 
  than 
  the 
  

   other 
  ; 
  both 
  are 
  straight 
  or 
  slightly 
  curved 
  upward 
  and 
  forward. 
  The 
  lower 
  

   pair 
  exist 
  only 
  in 
  the 
  males, 
  they 
  are 
  very 
  slender, 
  and 
  filiform, 
  and 
  quite 
  short. 
  

  

  •Published 
  in 
  advance, 
  March 
  3d, 
  1874. 
  • 
  

  

  