3 1 2 Geological Society : — 



clay-slates, and points out that four distinct stages must be con- 

 si tic red in the series of changes by which the rocks in question have 

 acquired their present character : — 1st, the deposition of the mud ; 

 2nd, the formation of minerals during the plastic state ; 3rd, the 

 separation of materials during solidification ; and 4th, the action of 

 metamorphic processes. 



6. " On a Section through Glazebrook Moss, Lancashire." By T. 

 Mellard Eeade, Esq., F.G.S. 



The section described has been exposed in a cutting made by the 

 Wigan Junction Railway. The moss rests on an almost perfectly 

 level floor of Boulder-clay, and is at the deepest part about 18 feet 

 thick. In the 3 or 4 feet at the base are branches &c. of trees ; and 

 the stools are found resting on and rooted in the Boulder-clay; 

 these are of oak or birch. Prostrate trunks were found, one, an 

 oak, being 46 feet long and 3 in diameter. The surface of the clay 

 is about 60 feet above O.D. The author thinks the section shows 

 that the moss originated from the decay of the forest, favoured by 

 change of climate, and gradually extended itself from the centre 

 outwards, trees within it at the outer part being much less dis- 

 coloured than those further in. In the latter part of the paper 

 some cuttings and borings in the clays and sands are described, and 

 the asserted occurrence of the trunk of a tree in the Boulder-clay is 

 noticed. 



7. " On the Tertiary Deposits on the Solimoes and Javary Kivers 

 in Brazil." By C. B. Brown, Esq. With an Appendix by It. Ethe- 

 ridge, Esq., F.R.S., F.Gr.S., and communicated by him. 



The author in 1874 had the opportunity of examining some beds 

 on the Solimoes, or Upper Amazon, and the Javary, one of its 

 tributaries, containing fresh- and brackish-water shells similar 

 to those found in Tertiary deposits at Pebas, still higher up the 

 river. The author indicates certain errors into which he considers 

 previous writers to have fallen, and calls attention to the great 

 extent of these beds, now demonstrated to occupy a tract of country 

 300 miles in length by 50 miles in breadth, and to the enormous 

 change in the physical features of the region which must have taken 

 place since their deposition. "When this took place the sea reached 

 probably 1500 miles west of its present shore-line, covering the 

 country which is now the valley of the Amazon. The absence of 

 examples of false-bedding in the deposits leads him to the conclusion 

 that they were formed in comparatively still water, into which 

 flowed numerous streams bearing much vegetable matter, which has 

 served for the formation of lignitic deposits, the whole being pro- 

 bably the upper beds of a series deposited under similar conditions 

 to those of deltas in the present day. In an appendix, Mr. Etheridge 

 notices the fossils collected by the author, which included seeds of 

 Chara, and species of Mytilus (1 new), Anisothyris (4, 1 new), 

 Lutra-ria (1), TTiracia (1), Anodon (1), Unio (1), Natica? (1), 

 Neritina (2 new), Odostomia (1), Hydrobia (1 new), Iscea (1), Dyris 

 (1), Assirninea (1 new), Fenella (1), Cerithium (2 new), Melania 4( 



