ALL our Vaccinieæ and Ericaceæ, with tubular corolla, as far as hitherto known, are adapted to cross fertilization by Apidæ; for instance, Vaccinium myrtillus and Vitis idæa, Arctostaphylos uva ursi and Erica tetralix. I was, therefore, much struck yesterday by the observation that Erica carnea is abundantly visited and cross fertilized by a butterfly, Vanessa cardui, but not by a single bee. And, indeed, the colour and structure of this flower corresponds far more to the taste and habits of butterflies than of Apidæ. Like all other alpine flowers adapted to butterflies (Saponaria ocymoides, Silene acaulis, species of Dianthus, etc.), Erica carnea is also of a gay red (pink) colour, and its inclined tubular corolla is so narrowed downwards that its small opening is almost completely occupied by the anthers projecting from it. Hence butterflies which are most distinctly attracted by the colour of this flower, as also by its structure, are alone able easily to insert their thin proboscis into its corolla and to reach its honey.