Reviews of the first edition: This paperback is, in general, well written and easy to read, especially as an introductory text for students ... A service to plant physiology has been well performed. This reviewer commends this little book as being 'a window upon the soul' of stomata ... - Journal of Experimental Botany; [Willmer] gives a highly readable, excellently illustrated account of the distribution, anatomy, structure and development of guard cells ... I know of no other review of the structural aspects of this range and elegance - Times Higher Education Supplement; Dr Willmer has produced a neat, crisply written monograph which will serve up to first degree level in all plant sciences for a good while to come - Biologist