Geological Society of London. 377 
bed b. From bed d Mr. Clement Reid obtained ‘seeds of 29 species 
of flowering plants. These are all marsh or aquatic species, except 
the hawthorn and dandelion. Unlike those found in Professor 
Prestwich’s bed d at Hoxne, there are no Arctic forms among them ; 
but the author pointed out that the Arctic plants of Hoxne were 
determined from leaves found in laminated clays, while the matrix 
in which the plants are found at St. Cross is only suitable for the 
preservation of seeds. However, certain of the plants do not range 
far north, and the occurrence of a large tree in the upper part of 
bed d points to a less rigorous climate than that under which the 
leaf-bearing beds at Hoxne were deposited. 
The lacustrine beds now occupy a ridge between two depressions, 
the valleys having been deeply eroded, or perhaps formed since the 
_ filling-up of the lake. It appears probable that on the final retreat 
of the last ice-sheet the hollows of the Boulder-clay were occupied 
by a series of lakes and pools. For the most part the sedimentary 
deposits formed in these hollows have been entirely swept away ; but 
at Saint Cross the mud and loam of one such lake have been preserved. 
2. “On certain Chelonian Remains from the Wealden and 
Purbeck.” By R. Lydekker, Esq., B.A., F.G.S. 
In the first part of the paper the author described a portion of 
the hind lobe of a Chelonian plastron from the Wealden, which was 
remarkable as showing a median row of epidermal shields. The 
name of Archeochelys valdensis was proposed for the form so repre- 
sented. The new generic term Hyleochelys was also proposed for 
the Purbeck Chelonian described by Sir R. Owen as Pleurosternum 
latiscutatum, and was also taken to include some other forms from 
the Wealden. 
The second section of the paper treated of the affinities of Plewro- 
sternum. It was concluded that Digerhhum, Cope (as represented by 
the so-called Platemys Bullocki), is identical with Pleuwrosternum, of 
which there appears to be only one Purbeck species. Evidence was 
brought forward to show that in the adult of Plenrosternum the 
pubis had a facet of articulation with the xiphiplastral ; and it was 
proposed to refer this genus, together with Platychelys and Baéna, 
to a new section termed « Amphichelydia,’ > which was regarded as 
allied both to the true Cryptodira and to the Pleurodira. 
3. “On the Relation of the Western Beds or Pebbly Sands of 
Suffolk to those of Norfolk, and on their Extension inland ; with 
some Observations on the Period of the final Elevation and Denuda- 
tion of the Weald and of the Thames Valley.” By Prof. Joseph 
Prestwich, M.A., D.C.L., F.R.8., F.G.S. Part I. 
The author in this, the first part of his paper, described the 
Westleton beds of the Hast Anglian coast. He commenced with a 
review of the work of previous writers, especially Messrs. Wood and 
Harmer, and the members of H.M. Geological Survey, including 
Messrs. H. B. Woodward, Whitaker, and Clement Reid. In dis- 
cussing this work, particular attention was paid to the Bure-valley 
beds, which were considered as a local fossiliferous condition of the 
Pebbly Sands; but the term is not so applicable to these sands as 
