480  Some  Notes  on  Chondrus.  {A  ootSbei.Pi899r.m' 
which  the  green  color  is  manifest ;  in  all  the  others  it  is  hidden  by 
means  of  other  coloring  substances,  to  which  are  given  the  various 
names  "  blue-green,"  "  brown  "  and  "  red."  The  blue-green  algae 
are  generally  found  in  moist  soil  near  fresh  water,  seldom  do 
they  occur  in  salt  water.  The  green  algae  represent  a  rather 
ubiquitous  group  that  may  be  said  to  be  found  anywhere  where 
the  conditions  for  C02  assimilation  are  present.  The  brown  algae, 
represented  by  Fucus,  Laminaria,  Sargassum,  etc.,  reach  their 
greatest  perfection  in  the  colder  waters,  as  north  of  Cape  Cod  and 
the  English  channel.  The  red  algae  attain  their  greatest  perfection 
in  the  deeper  waters. 
The  outer  morphology  of  the  algae  appears  to  be  rather  simple. 
They  may  consist  of  a  single  row  of  cells  placed  end  to  end 
and  forming  thread-like  masses,  as  Lyngbya  (called  mermaid  hair), 
or  cord-like  masses,  as  in  Chorda.  In  some  cases  the  thread-like 
filaments  may  branch  as  in  Griffithsia.  The  same  may  be  said  of 
some  of  the  algae  which  are  made  up  of  a  large  number  of  cells 
placed  side  by  side,  as  Ceramium,  Dasya.  In  some  cases  the  thallus 
is  flattened,  as  in  Chondrus,  Laminaria,  Rhodymenia.  In  some  cases 
the  parts  of  the  plant  are  differentiated  to  such  an  extent  that  there 
is  developed  what  looks  like  root  ("  hold-fast  "),  stem  ("  stipe  ")  and 
leaf  ("  blade  "),  as  in  Laminaria.  In  some  cases  there  are  incrusta- 
tions of  calcium  carbonate  produced,  as  in  Melobesia,  Corallina. 
In  regard  to  manner  of  reproduction  in  the  algae  we  have  a  num- 
ber of  distinct  kinds  of  sexual  and  nort-sexual  reproduction.  It  is 
not  fitting  that  I  take  up  these  different  forms  at  this  time.  In  the 
sexual  mode  of  reproduction  we  have  essentially  three  kinds:  (i) 
The  conjugation  of  two  cells  that  look  essentially  alike  ;  (2)  the  con- 
jugation of  two  cells  that  may  be  distinguished  one  from  the  other, 
and  to  which  the  terms  male  and  female  are  applied,  and  (3)  the  re- 
markable condition  such  as  we  find  in  the  red  algae,  as  in  Chondrus, 
Gigartina  and  some  others  in  particular,  and  which  will  be  briefly 
described  presently. 
In  its  general  outer  morphology  Chondrus  crispus  (L.),  Stack., 
consists  of  more  or  less  purplish  colored  fronds,  which  are  from  2  to 
4  inches  long,  dichotomous,  flat,  the  segments  being  linear-cimeate. 
It  is  attached  to  the  rocks  by  a  slender  hold-fast,  and  has  not  infre- 
quently been  found  growing  upon  various  forms  of  marine  life.  On 
making  a  transverse  section,  we  observe  a  more  or  less  differentiated 
