Have contemplated writing a book though actually. Main idea is a comprehensive field guide for the amateur mushroom forager out to harvest himself some supper, but also for those interested in the likes of ergot chemistry, fungal toxicology in general, data on lab techniques for culturing things, making spawn, sterile working and stuff like bioengineering w/fungi, microscopy (about time I had myself a good reason to get his microscope out.
A handbook detailing reagent testing of fungi in the field, or at home would be very useful to others IMO, if they are fellow mycophiles, Not just for some UK/european macrofungi species, but something more specialist, just for the reagent identification data and for microscopy, such a specialist guide would have come in really, really useful to toady, most field guides either barely touch on the use of chemicals, stating that such falls outside the scope of the non-professional mycologist, or for the more comprehensive, detailed and in-depth gruide, such as Phillips (spotted a few errors in his work however, such as for example, stating Mycena pura is edible. It isn't, and whilst not anywhere near as much so as most of the Inocybes, but M.pura does contain muscarine, and has caused quite a few cases of poisoning, neglects to warn against the consumption of the man on horseback [Tricholoma flavovirens, syn. T.equestre], which certainly used to be one of the more highly regarded edibles, yet it contains a cyclopropene-based small molecule toxin that causes rhabdomyolysis (direct myotoxic injury, causing destruction of muscle tissue, the breakdown products of which then go on to work over your kidneys, potentially causing kidney failure.
I forget the exact structure of the toxin, but its the same substance as is found in the notoriously toxic japanese mushroom species, Russula subnigricans, another myotoxic mushroom. But the man on horseback, or knight on horseback, Tricholoma flavovirens doesn't seem to cause instant poisoning upon eating it, and as such was regarded as edible and choice for quite some time, But when people eat the species in multiple meals over a short period of time, being greedy basically, then it can start lysing muscle and shutting down kidneys.
Phillips claims its edible and good eating, and although not specifying especially, unusually good, also names those two hygrocybe spp (the hygrocybes, and hygrophorus spcies are commonly called waxcaps due to the greasy or slippery texture of the caps, especially when wet, there are some good ones to be had, Toady used to enjoy going to his grandma's house when she was still alive to stay over for things like xmas, b/days and generally speaking the family going to do social to them, because it meant he could go out with a pocket full of bin bag rubbish sacks, and come back with a truly gigantic crop of waxcaps from up on the yorkshire moors, especially Camarophyllus pratensis, the meadow wax-cap,, scarlet hoods and crimson waxcaps, all three of which are very tasty; the meadow waxcap most of all, which is quite a bit bigger than the rest of the waxcaps, or at least most of them, and it has quite a nice texture, with a delicate, but very pleasant flavour indeed after rinsing off any organic debris, and throwing them into a frying pan with a knob of salted butter, maybe just a pinch of very finely ground black pepper, sprinkled very finely over them, although they are perfectly good to eat without any seasoning at all, short of some butter in which to fry them, and maybe a bed of beans, rice, maybe some chickpeas for something on which to serve one's hard-foraged harvest.
Phillips makes a couple of significant errors regarding waxcaps, stating the conical, and the blackening wax cap are edible. Again they are not, although quite the extent of how poisonous they are isn't known for certain, but that they are, is certain.
Lists some Galerina and Conocybe species as merely inedible, IMO given how toxic they are, being full of amatoxins, a full warning is not only justified, but had Tsath written Phillips' book rather than the man himself, it would have been obligatory.