76 Origin of the British Flora. 
Corylus Avellana. Potamogeton compressa. 
Quercus sessiliflora. ——- obtusifolia. 
Fagus sylvatica. —-———- pusilla. 
Salix. ——_——- rutila. 
Populus tremula. —_—__—_—_-. cf. trichoides. 
Platanus (?). — marina. 
Najas major. 
— flexilis. 
Scirpus lacustris. 
Eriophorum vaginatum (?). 
Carex acuta (?). 
— cf. acutiformis. 
— rostrata. 
Phragmites communis. 
Taxus baccata. 
Juniperus communis. 
Pinus sylvestris. 
Abies pectinata. 
Juglans regia (?). 
Empetrum nigrum. 
Ceratophyllum submersum. 
demersum. 
Typha. 
Sparganium minimum. 
— simplex. 
Potamogeton natans. 
———- cf. polygoni- 
folia. 
Potamogeton rufescens. 
— cf. colorata. 
——_--——_ graminea. Picea excelsa. 
——_—+——- cf. prelonga. Equisetum palustre. 
— perfoliata. Polystichum cf. Thelypteris. 
———-- —— crispa. 
HORNSEA, YORKSHIRE. 
(Phillips, ‘Geology of Yorkshire, 3rd edit. Part I., 
pp. 75-79. 1875; Reid, ‘Geology of Holderness, Mem. 
Geol. Survey, pp. 79-83. 1885.) 
Peaty mud fills a valley cut through the Glacial 
deposits. It contains Mammoth (?), Irish Elk, Lion, and 
Bos primigenius (?). The mollusca and plants are all 
recent British forms. 
Prunus Padus. 
Alnus glutinosa. 
Quercus Robur. 
Pinus sylvestris. 
Potamogeton. 
Chara. 
Salix. 
The stratigraphical position of this deposit and its resem- 
blance to other ‘Submerged forests’ suggest a Neolithie or 
Late Glacial Age. The occurrence of the Mammoth, Lion, 
