re store pictures in an automatically named files using loops

Dear all:
     I hope that the file in which the picture is stored has the same name
as the " main" title of the picture . But it turns out that , the name of
the file is :names(spl.sp)[i].bmp,while the main title of the picture is
names(spl.sp)[i+1]
 It seems that the problem is related to the "device". But I am finding it
very difficult to understand .
  Do you have any idea about that?

Here is my function:
 
sp.drawK<-function(spl.sp){
env<-list() 
for(i in 1:length(spl.sp)){
if(spl.sp[[i]]$n==1) next
else{
env[[i]]<-envelope(spl.sp[[i]],Kest)
  plot(env[[i]],main=names(spl.sp)[i])
  legend("topleft",lty=1:4,col=1:4,legend=c("obs","theo","hi","lo"))
  text(2,500,cex=0.8, paste("n=",spl.sp[[i]]$n,sep=""))
  bmp(paste(names(spl.sp)[i],".bmp",sep=""))

  }
}
}

   Best wishes,
  Bin Yue