Page:Memoirs of the Geological Survey of Great Britain, Volume 1.djvu/352

Rh number of plants of the same climatal type with those enumerated above, but whose range does not extend beyond this corner of England. Such are Helianthemum polifolium, Tamarix gallica, Hypericum linearifolium, Oxalis corniculata, Lotus hispidus, Corrigiola littaralis, Polycarpon tetraphyllum, Bupleurum aristatum, Physospermum cornubiense, Lobelia urens, Erica ciliaris, Salvia clandestina, Trichanema columnæ, and Scilla autumnalis.

In the south-east of Ireland we find the number of plants of this Gallican type greatly diminished; whilst such as are present are species met with also in the south-west of England. Such are Matthiola sinuata, Senebiera didyma, Medecago denticulata, Rubia peregrina, Antirrhinum orontium, Linaria elatins and italica, Scrophularia scorodonia, Sibthorpia Europæa, Erica vagans, Cicendia filiformis, Teucrium scordium, Hottonia palustris, and others.

This is the Atlantic type in Mr. Watson's arrangement of British types of vegetation.

Helix pisana extends its range through a great part of this region. Testacellus haliotoideus is confined to the English portion of it. This was possibly the parent British fauna of Bulimus acutus. The presence of the Bufo calamita (the Natter Jack) in Ireland is probably also proper to this province.

III. In the south-east of England, where the rocks of the cretaceous system are chiefly developed, we find the vegetation distinguished by the presence of a number of species common to this district and the opposite coast of France. Here are the localities of the well-known chalk plants, much sought after by botanists from the north. They form part of Mr. Watson's second, or Germanic, and of his third, or English, type of British vegetation.

Thlaspi perfoliatum, Linum perenne, Genista pilosa, Onobrychis sativa, Bryonia dioica, Caucalis daucoides, Dipsacus pilosus, Inula conyza, Centaurea calcitrapa, Phyteuma orbiculare, Gentiana pneumonanthe, Verbascum lychnitis, thapsiforme, and blattaria, Salvia pratense, Ajuga chamæpitys, Buxus sempervirens, Tamus communis, and many species of Orchideæ, though not all chalk plants, are members of this flora. Clematis vitalba, and some other plants, appear to be equally members of it, and of the last region.

The peculiar character of the entomology of the south-east of England is intimately connected with the presence of this flora, and also that of the pulmoniferous mollusca, which here include several species, as Helix pomatia, Helix obvoluta, Helix limbata, Helix carthusiana and carthusianella, Clausilia ventricosa, Clausilia Rolphii, and Bulimus montanus, either confined to this district, or very rarely found beyond it in Britain.