Am.  Jour.  Pharm. 
May,  1887. 
Bahama  Sponges, 
261 
the  surface  of  the  water,  and  sometimes  are  irregular  or  dendritic  in 
shape,  and  are  then  much  less  valuable.  Those  known  as  reef  sponges 
are  similar  in  shape  to  the  glove  sponge,  but  are  rather  harder,  and 
have  the  oscules  more  regularly  distributed  over  the  surface.  Old 
specimens  become  very  brittle  and  are  easily  torn.  A  third  kind,  scarcely 
distinguishable  from  the  glove  sponge  by  the  eye,  but  harder  even  than 
the  reef  sponge  to  the  touch,  is  described  as  a  "  hardhead  "  sponge. 
Sheeps'  Wool. — This  variety  corresponds  most  nearly  with  the 
honeycomb  sponge  of  the  Mediterranean,  and  is,  indeed,  an  Ameri- 
can variety  of  that  sponge.  It  derives  its  name  from  the  fact  that 
the  fibres  of  the  external  surface  are  developed  in  the  form  of  little 
pointed  tufts,  which  give  the  sponge  a  peculiar  fleecy  appearance. 
In  its  sub-spheroidal  shape  it  resembles  the  Mediterranean  honey- 
comb sponge  ;  the  larger  apertures  are  distributed  with  comparative 
regularity  over  the  upper  surface,  the  fleecy  tufts  sometimes  project- 
ing and  converging  over  the  openings  ;  the  inner  substance  is  honey- 
combed with  tortuous  channels.  This  sponge  is  soft  to  the  touch  and 
is  suitable  for  bath  and  toilet  use,  but  is  only  one-half  the  price  of  the 
Mediterranean  honeycomb  sponge.  It  is  found  at  depths  varying 
from  three  to  sixteen  feet  or  more,  the  finest  in  size  and  fibre  being 
found  at  the  greatest  depth.  A  sponge  very  similar  in  appearance  to 
the  sheeps'  wool,  but  much  harder  to  the  touch,  is  met  with,  which 
is  classed  as  a  a  hardhead  "  sponge. 
Abaco  Velvet  or  Boat  Sponge. — This  sponge  bears  a  general  re- 
semblance to  the  sheeps'  wool  in  shape  and  size,  but  the  superficial 
tufts  of  fibres  stand  out  more  distinctly  and  are  more  obtuse  and  some- 
what broader.  The  most  marked  feature  consists  in  the  oscules  be- 
ing crowded  in  the  centre  of  the  sponge  and  there  uniting  to  form  one 
or  more  rarely  two,  large  openings  which  much  depreciate  its  value. 
If  the  opening  is  closed  by  passing  a  thread  round  it  and  then  draw- 
ing the  sides  of  the  aperture  together  the  sponge  will  last  much  longer. 
In  texture  it  is  as  soft  as  the  sheeps'  wool ;  it  is  quite  suitable  for  toi- 
let use,  where  a  cheap  sponge  is  required,  and  is  about  25  per  cent, 
cheaper  than  the  sheeps'  wool. 
Cay  Velvet — This  sponge  is  a  harder  variety  of  the  Abaco  velvet, 
being  much  more  resistant  to  the  touch.  It  presents  in  a  still  more 
marked  manner  than  that  sponge  the  peculiar  appearance  like  brain 
coral  (Meandrina)  which  characterizes  the  velvet  sponges.  It  is  chiefly 
used  by  painters  and  for  stables  and  domestic  cleaning  purposes. 
