The Trias will ever be memorable for the commencement of the mighty change in the order of life; side by side with the clumsy and horrid Labyrinthodon appeared the tiny Microlestes, with its small body and larger brain; henceforward the battle would rage between the mammal with its specialised brain, and the reptile with its gigantic body; and geological history has recorded how, though the air, the land, and the water, were peopled with reptiles of greater size and development, through the Trias, the Oolite, and the Chalk, yet the small mammals ever increased in variety and number until, when the great Chalk Ocean receded, and the Eocene period dawned, the age of reptiles had passed away, and the tide of mammalian life had set in, differentiated into the forms of the present day.

MARINE PLANTS OF DROITWICH AND DISTRICT.

Anyone who has collected the flora of central Worcestershire must have been impressed with the presence of the numerous marine plants growing in the heart of England, so many miles distant from the sea coast. It is now generally admitted by geologists that in comparatively recent geological times Wales was separated from England by a shallow marine strait, which occupied to a great extent the valley of the Severn, and as its waters washed the foot of the Malvern Hills, Sir R. Murchison designated it the Straits of Malvern. There is evidence of its presence all down the Severn Valley in the terraces of gravel on each side of the river, at a considerable height above the present bed, and in the erosion of the Red Sandstone Cliffs at Bridgnorth, and also below Stourport. As the land became elevated the sea gradually receded, leaving the valley occupied by a marine estuary, which has left traces behind, not only in sand and gravel and pebbles, but also in accumulations of broken shells. The late Edwin Lees states that the sandpit at Northwick, near Worcester, abounds with fragments of broken-up shells, in almost as great quantities as at Weston-super-Mare, or on the sands at Tenby. As the land rose farther salt marshes occupied the ground lately covered by the sea all down the banks of the Severn, wherein flourished all the salt-loving plants, and though the marshes have been drained for cultivation we still have surviving in the county marine plants which tell the story of the Malvern Straits and Estuarine period. On the sand dunes of Hartlebury Common we still find Buck's horn plantain, Plantago coronopus, Erodium maritimum, Sea Storks-bill, Erodium cicutarium, Hemlock leaved Storks-bill, and Naked stalked Teesdalia, Teesdalia nudicaulis. Edwin Lees, in his Botany of Worcestershire, mentions many marine plants growing in the Severn Valley, which have survived since the estuary receded :--Sea Stork's Bill, Erodium maritimum at Hartlebury Common, Habberley Valley, and Trimpley Green, near Kidderminster. Burnet Rose, Rosa spinosissima, on sandy soil near Kidderminster; narrow leaved Hare's Ear, Bupleurum tenuissimum, on Welland Common; Callous fruited Dropwort, Enanthe pimpinelloides at Powick; Lachenal's Parsley, Water Dropwort, Enanthe Lachenalii, Defford Common, and Welland and Longdon marshes; Salt-Marsh Brookweed, Samolus

Valerandi, Defford and Fladbury; Sea-Dock, Rumex-maritimus, Longdon Marshes and Severn, near Worcester; Salt Marsh Club Rush, Scirpus maritimus, Longdon marshes; Shore weed, Littorella lacustris, Longdon marshes. But the river Salwarpe and Droitwich Canal below the town are exceedingly rich in marine specimens, where they flourish in the salt water discharged into the river and canal from the Saltworks: the following are mentioned by the same authority :-Salt Marsh Club Rush, Scirpus maritimus; Reflexed Meadow Grass, Poa distans; Broad-leaved Pepperwort, Lepidium latifolium; Narrow-leaved Pepperwort, Lepidium ruderale; Wild Celery, Apium graveolens; Saltwort, Glaux maritima; Sea Orache, Atriplex rosea; Sea Sandwort, Spergularia marina. I have found Lepidium ruderale at Tardebigg, eight miles nearer Birmingham, on the side of the Canal, the seeds doubtless having been carried thither by passing boats.