This post is part of an ongoing series featuring items recently cataloged from the Julio Mario Santo Domingo Collection.
Mushrooms- they are cheap and legal, but how do you ensure that you don’t eat the wrong one? Hallucinogenic Mushrooms contains information on identification, buying and eating mushrooms, different species, current laws, as well as poisonous mushrooms in Britain.
This handy guide counsels that there is no one test to figure out if a mushroom can be safely eaten. A common myth is that poisonous ones will blacken a spoon, while edible mushrooms peel easily, and “magic” mushrooms turn blue after they are uprooted. Be warned this publication states that None of these tests can be relied on!
They suggest that you should go with an experienced identifier until you know your stuff. And getting a comprehensive fungi guide such as Collins Guide to Mushrooms and Toadstools is a good idea or if you are looking for “magic” mushrooms they recommend A Guide to British Psilocybin Mushrooms (both can be found in the Botany Libraries for reference.) 
Once you have your identification books with you it will be easier to identify fungi in the field. The physical features of the mushroom hold the key, step one is to look at the cap and observe its shape and color, then determine if the surface is shiny or dull and if there are lines. To get a look at the flesh break off a bit, smell it, and note the color of the gills and how they are attached to the stem. What shape and color are the stem? Are there rings on it? Is there a bulb at the bottom? Always make sure that it is a mature specimen because a great deal of fatal cases of mushroom poisoning happen when people pick a mushroom before it is fully developed because characteristics revealing its poisonous nature may not yet be present.
Mushroom poisoning can be observed as quickly as 20 minutes after eating or as late as 40 hours, the later it takes symptoms to show the more serious the situation because the poison has had time to circulate within the body. Medical advise should be sought immediately even if you begin to feel better because is a characteristic of the poison to have periods of recovery followed by eventual demise.
Hallucinogenic mushrooms : a Release guide
/ written by the Release Collective ; illustrations by Grant. London : Release, 1979 can be found in Widener’s collection.
Thanks to Alison Harris, Santo Domingo Project Manager for contributing this post.