The curious little edible Agaricus esculentus, although placed under the sub-genus Collybia, is allied by its structure to Marasmius.
Though fruit-trees will not bear there is an abundance of edible berries; the rivers and lakes abound with trout, perch, pike and other fish, and in the lower waters with salmon; and the cod, herring, halibut and Greenland shark in the northern seas attract numerous Norwegian and Russian fishermen.
Among indigenous trees, shrubs and vines that bear edible fruits or nuts the state has the blackberry, grape, pawpaw, persimmon, plum, crabapple, hickory, chestnut and hazel nut.
One of the last (Collocalia troglodytes, Gray) constructs the edible nests so highly prized by the Chinese.
The importance of sun heat to the general well-being of plant life, its influence on the production of flowers and the ripening of edible fruits, has long been appreciated in horticulture.
Many edible fungi depend upon minute and often obscure botanical characters for their determination, and may readily be confounded with worthless or poisonous species; but that is not the case with the common mushroom, for, although several other species of Agaricus somewhat closely approach it in form and colour, yet the true mushroom, if sound and freshly gathered, may be distinguished from all other fungi with great ease.
The contents of the nut are edible as in the coco-nut.
On the continent of Europe the largest oil-trading centres are on the Mediterranean (Marseilles and Triest), which are geographically more favourably placed than England for the production of such edible oils (in addition to the home-grown olive oil) as arachis oil, sesame oil and coco-nut oil.
Besides valuable contingents of the celebrated Balearic slingers, the Romans derived from their new conquest mules (from Minorca), edible snails, sinope and pitch.
Corylus rostrata and C. americana of North America have edible fruits like those of C. Avellana.