Dear Michael Miller, Thanks for your message. You have the advantage over me as it was some 50 years ago that I was at the R.B.G. Edinburgh, and you jolted my memory regarding things! I almost said how soon we forget, but 50 years is a while! So perhaps there is a reason for forgetting such things. Now I remember why pines have sunken stomata and a host of other such adaptations of plants all contributing to them being able to withstand adverse conditions, Thanks, I needed that! Cheers and good wishes for 2005. Here in California we are getting enough rain to satisfy us for a while, yet more is on the way. John E. Bryan