TAXONOMY AND NOMENCLATURE IN SOME SPECIES OF THE GENUS ARUM L.

two as separate species. The differences between the two have been discussed by Ridley (1938) but plants intermediate in every respect can be found in large populations on the Continent, and in the extreme west of England. There is a ratio dine, the italicum form being commoner in the Mediterranean area, and the neglectum form in south Britain. Particularly attractive forms of Arum italicum with dark green leaves, diverging basal lobes and a well-marbled white venation have been cultivated in this country and are occasionally found as escapes. This fact complicates the interpretation of the distribution in the British Isles, but the main facts of the cline are clear enough, and it seems best to treat the two as SUbspecies. The first real attempt to classify the common Aroids was made by Tournefort (1719). He describes three genera, Arum, Dracunculus and Arisarum. Linnaeus's copy of this book, now in possession of the Linnean Society, contains his names against the species listed, and he included them all as belonging to the single genus Arum. Tournefort gives the synonymy for Arum maculatum and amongst the names may be noted 'Arum venis alhis C. B. Pinax ' and 'Arum venis alhis, ItaUcum, maximum, H. R. Par. ' (See Bauhin, C