Some such species are Blechnum boreale, Aira flexuosa, Calluna vulgaris, Vaccinium, Myrlillus, Rubus, Chamaemorus, Empetrum nigrum, Drosera spp. Some, at least, of these species possess mycorhiza in their roots, and are perhaps unable to live in soils where such organisms are absent.
Such are the crowberry (Empetrum nigrum), Trientalis europaea, Rubus saxatilis and the globe-flower (Trollius europaeus).
Pliny treats of these two metals as plumbum nigrum and plumbum album respectively, which seems to show that at his time they were looked upon as being only two varieties of the same species.
PIPERINE, C17H,9N03, an alkaloid found in the fruits of Piper nigrum and P. longum.
From Pliny's writings it appears that the Romans in his time did not realize the distinction between tin and lead: the former was called plumbum album or candidum to distinguish it from plumbum nigrum (lead proper).
Myrmecium nigrum, which is an accurate copy of the large black ant (Pachycondyla villosa).
Nigrum, 2 to 3 ft., has blackish-purple flowers, also V.
Nigrum, but the hybrids proved as susceptible as the potato itself.