This section is from the book "Our Edible Toadstools and Mushrooms and How to Distinguish Them", by W. Hamilton Gibson. Also available from Amazon: Our Edible Toadstools And Mushrooms And How To Distinguish Them.
The remainder of my selection in the present chapter comprises scattered examples from four other orders: Hydnei (Spine-bearers), Clavariei (Coral-fungi), and the Trichogastres (Puff-balls), all belonging to the first great division of the Sporifera. The remaining two species considered - Morel and Helvella, of the order Elvellacei - are my only representatives of the second grand cohort of the Sporidiifera, whose botanical characters are described on page 77.
In our previous examples the hymenium or spore-bearing surface has been disposed upon "gills," as in the Agarics, and on "tubes" in the Polypores. In the Hydnei group, which we will first consider, this disseminating surface is spread over spines or teeth.
The examples selected from this order are both in the typical genus Hydnum; and the object of this present book on fungi being especially the presentation of only such varieties as are conspicuously self-placarded by some distinctive marks for identification, these delicious spine-bearing or "hedgehog" mushrooms should of course be included - a genus which cannot be mistaken for any other, and which is instantly recognized by its own peculiar character, already mentioned, its spore surface being beset with soft, drooping spines instead of pores or gills. There are more than a score of species. The two more or less common with us are the Hydnum repandum, in outline suggesting an ordinary mushroom, and of which the above cut represents a section, and the Hydnum caput-medusa, or Medusa-head Hydnum. None of the group is accounted poisonous, though some of them are too tough to be acceptable as food.