图如下，在legend中有连个条线和两个点，希望将绿色和橘色的点线都在legend中标出，蓝色与红色的点不变。
问如何修正。


下
代码如下：

library(gridExtra);
require(reshape);
require(ggplot2);

a <-c(0.61,0.57,0.78,1.36,0.85,0.53,0.45,0.19,0.08) #names
b <-c(0.23,0.26,0.55,0.56,0.36,0.23,0.18,0.06,0.04) #mean t0
x <-c(0.64,0.6,0.81,1.4,0.89,0.55,0.48,0.22,0.09) #mean t1

da <- data.frame(a,b,x)
da1 <- melt(da, id="x")

x1<- c(0.81,0.81)
y1<-c(0.5,0.8)
da2 <- data.frame(x1,y1)

ggplot()+
geom_line(data=da1,aes(x=x,y=value,group=variable,linetype=variable,color=variable),show_guide = FALSE)+
geom_point(data=da1,aes(x=x,y=value,group=variable,color=variable, shape=variable),show_guide = FALSE)+

geom_point(data=da2,aes(x=.81,y=c(.5,.8),color=as.factor(y1)),size=3)+
scale_color_manual(values = c( "red", "blue", "darkgreen","orange"), labels = c("four", "six", "eight","55")
)