SIRVERSIA.  A  genus  of  BoiaeecB,  usually
unUed  with  Oeum,  but  differing  in  the
styles  being  Jointed,  the  upper  Joint
dissimilar  to  the  lower,  and  usually  de-
ciduous. 8.  montana  from  Austria  and
8.  reptans  from  Switzerland  are  cultivat-
ed ;  they  are  herbaceous  plants  about  six
inches  high,  with  leaves  like  those  of  a
Oeum,  and  large  solitary  handsome  yellow
flowers.  [0.  A.  J.]

SIGMOID.  Having  a  form  somewhat
resembling  the  letter  S.
8ILAUS.  A  genus  of  Umhelliferce,  dis-
tinguished by  each  half  of  the  fruit  having
Ave  sharp-edged  equal  ribs  with  numerous
vitts  in  each  furrow,  and  four  to  six  at
the  line  of  junction.  The  species  sre
perennial  herbs,  natives  of  Europe  and
Asia.  Their  leavesare  usually  in  numerous
narrow  or  linear  subdivisions.  The  name
was  used  by  Pliny  to  indicate  some  umbel-
liferous plant.  [G.  D.]

SILBADANI.  A  furniture  wood  of  De-
merara.
SILENE.  An  extensive  genus  of  herba-
ceous plants  belonging  to  the  tribe  Silene(e


of  CaryophjfUaeea.  The  species  agi*ee  in
the  following  characters :— Sepals  united ;
stamens  ten ;  capsule  stalked,  dry,  opening
at  the  top  with  six  teeth ;  styles  three  to
four  Of  the  British  species  the  most
frequent  is  8.  vitfUUa,  or  Bladder  Campion,

P€  tro

fe  eU


ts.
It

Species  indigenous  to  various  temperate
countries  of  the  Eastern  and  Western
Hemispheres  are  occasionally  cultivated,
some  of  the  most  ornamental  being  8.
