Insectivorous Plants · Charles Darwin
PINGUICULA GRANDIFLORA.
This species is so closely allied to the last that it is ranked by Dr. Hooker as a sub-species. It differs chiefly in the larger size of its leaves, and in the glandular hairs near the basal part of the midrib being longer. But it likewise differs in constitution; I hear from Mr. Ralfs, who was so kind as to send me plants from Cornwall, that it grows in rather different sites; and Dr. Moore, of the Glasnevin Botanic Gardens, informs me that it is much more manageable under culture, growing freely and flowering annually; whilst Pinguicula vulgaris has to be renewed every year. Mr. Ralfs found numerous [page 391] insects and fragments of insects adhering to almost all the leaves. These consisted chiefly of Diptera, with some Hymenoptera, Homoptera, Coleoptera, and a moth. On one leaf there were nine dead insects, besides a few still alive. He also observed a few fruits of Carex pulicaris, as well as the seeds of this same Pinguicula, adhering to the leaves. I tried only two experiments with this species; firstly, a fly was placed near the margin of a leaf, and after 16 hrs. this was found well inflected. Secondly, several small flies were placed in a row along one margin of another leaf, and by the next morning this whole margin was curled inwards, exactly as in the case of Pinguicula vulgaris.
Text from Project Gutenberg, public domain in the United States.