622 PEOF. W. J. SOLLAS ON THE ESTUARIES OE 



spherules are precisely similar to those occurring in ancient sediments, 

 particularly limestones : they are described in my paper on the Silurian 

 district near Cardiff (Quart. Journ. Geol. Soc. vol. xxxv. p. 504). 

 The direct connexion of the pyrites with the vegetable matter is 

 beautifully shown by their frequent occurrence within the cells of 

 vegetable tissue, where they may be seen occupying the place of the 

 departed protoplasm, and surrounded on all sides by the persistent 

 cellulose cell-wall. 



The clay below the first peat is not yet clearly exposed in this 

 cutting. I have so far been able to examine it sufficiently to state 

 that it contains organic remains like those of the upper clay. 



The sand, six feet in thickness, is of a greenish blue colour and 

 consists of fragments of colourless quartz, with included cavities 

 and microliths, green grains, and numerous shelly fragments which 

 give it a white-speckled appearance. The most noticeable organic 

 constituents are abundant fragments of some species of Polyzoa ; 

 besides these are many chips of Lamellibranch shells, amongst 

 which I noticed a small broken Avicula, Foraminifera, spines of 

 Echinoderms, and sponge-spicules. 



The lower bed of peat is not yet exposed in the cutting. 



The lowest gravel consists of rolled pebbles, angular and subangular 

 blocks of Millstone Grit, vein-quartz, Mountain Limestone, and it 

 may be of other material. Some of the blocks are more than a 

 cubic foot in size, and one subangular fragment of Mountain 

 Limestone was found well smoothed and striated as if by ice. 



No. 8 is taken from a paper read by Mr. W. C. Lucy, before the 

 Cotteswold Club, March 6th, 1873. The blue clay is stated to have 

 yielded, at from four to six feet from the surface, nests of Tellina 

 solidula, a shell which abounds on some parts of the shores of the 

 estuary at the present day. The peat contained many trunks of 

 trees, chiefly oak, alder, beech, and hazel ; some of the oaks were of 

 great size. 



No. 9 is a section obtained in excavating the New Docks at 

 Cardiff. I have to express my best thanks for it to my friend 

 Mr. John Storrie, Curator of the Cardiff Museum, who has not only 

 generously sent me full information concerning it, but specimens for 

 examination. 



Below 4 J feet of made ground is blue clay, twelve feet thick, the 

 upper five feet full of Foraminifera, the lower seven feet charged 

 with disseminated vegetable matter, but still containing marine orga- 

 nisms. Next below is peat, from six to eighteen inches thick ; of this 

 I trust that Mr. Storrie, with his extensive botanical knowledge, 

 will furnish us with fuller information at some future time. It 

 is remarkably uncontaminated by mineral sediment, if I may judge 

 from the specimen in my possession ; only a few grains of angular 

 sand, and some sponge-spicules and Foraminifera occur in it. 



Below the peat is 22 feet more of blue clay, in its upper part 

 containing fewer Foraminifera than that above the peat, and many 

 of these are pyritized ; in its lower part are still fewer Foraminifera, 

 but many examples of Scrobicularia jjiperata. It is interesting to 



