The determination is based on a systematic study of the characteristics of fungi, the fcon botanists (eg Gaston Bonnier. Flore ... France and elsewhere). But as the botanists demand a solid base of knowledge to be able to find it, as it is accessible. However one must know a minimum of elements and vocabulary to understand what is written (eg stipe, jock, etc.). There is an excellent and essential glossary in the book with good descriptions. In other words, thinking that we can recognize with certainty a fungus without knowing anything about it, just by looking at pictures is a (dangerous) illusion. I know: I tried and I failed. There are so many subtleties and variability in characteristics between good and sometimes dangerous fungi that encourages mycologists caution. Furthermore, if there are pictures, they must be perfect: no sudden flash that crush the colors or staining the floodlight etc. In short, the challenge is not a foregone conclusion! The book of Marcel Bon is excellent. It is also a reference. Explanations contain fewer abbreviations and are therefore easier to read; it also uses a systematic but there is less and it is described mushrooms ... exhausted, as Flammarion, this sucks! Mycologists often use the 2 items. In short we must make an effort to get into the book but it is inevitable for anyone interested mushrooms. The format is fairly small so transportable. There are by the same author (with G. Bonnier) pocket guide that I did not know ... and therefore I will not, but given the level of the authors I'm not worried.
