TRANSACTIONS OF THE SECTIONS. 67 

| Mr. S. Stutchbury exhibited a large cylindrical bone found by Mr. Thompson of 
_ Aberdeen in the “ Bone-bed” of Aust Cliff on the Severn, and presented to the Bristol 
Institution. The strata at this spot consists of the insect limestone, landscape marble, 
and bone-bed of the lias, resting on the marls of the new red sandstone system. But 
since the fish remains in the bone-bed belong to the Triassic type, it may be equally 
well to compare any reptilian remains found in it with those of the new red sand- 
_ stone. The present bone, though wanting both extremities, is two feet in length, and 
more than five inches in diameter at one end, where it is broken off abruptly: it is 
unlike any bone of Chelonian or Enaliosaur, but presents some resemblance to the 
long bones of small recent Batrachia, on which account Mr. Stutchbury considers it 
referable to the great Labyrinthodon of the new sandstone. 


On the Cause of the general Presence of Phosphorus in Strata and in all fertile 
Soils ; also on Pseudo-Coprolites, and the Conversion of the Contents of Sewers 
| and Cesspools into Manure. By Tur Dean or Westminster, F.R.S. 
Since Liebig first suggested the application of fossil phosphates to the same pur- 
poses with recent bones and guano in agriculture, many inquiries have been directed 
to such localities as promised to afford a supply of bones, coprolites, &c.; the bone- 
bed of the lias, exposed on the shores of the Severn, has not yet been worked, and 
will not repay the cost of working, but the red crag of Felixstow on the coast of Suffolk 
has afforded many thousands of tons of phosphoric pebbles, mixed with bones of whales 
and elephants and other large mammalia, and with flint pebbles, siliceous sand and 
erag-shells; the phosphoric bodies show upon analysis a composition nearly identical 
with that of the true coprolite. The origin of the pseudo-coprolites in this remarkable 
deposit must be sought in a period antecedent to the crag, during which the London 
clay was in progress of formation, and when the muddy bed of the Eocene sea received 
daily accessions of phosphoric compounds from the dead bodies and féeces of fishes 
and Molluses which inhabited it. The remains of these creatures, decomposing in the 
_ mud, evolved ingredients which, combining with the surrounding sediment, became 
fixed in Septaria and smaller concretions. In deposits of siliceous sand no such com- 
_ binations could take place, and hence the barrenness of siliceous sands when converted 
- into dry land. Phosphate of lime exists largely in all organized bodies, and is soluble 
slowly in water charged with carbonic acid: we may assume that all sea-water con- 
tains it; it exists in marine vegetables, and in herbivorous and carnivorous fishes and 
_ Molluscs. The combination of these phosphates with the earthy concretion not only 
_ purifies the water of the ocean and maintains it in a state adapted for the existence 
_ of living things; it serves also to form a continually increasing store of fertility against 
_ the time when the sea-beds shall be elevated and converted into corn-fields. While 
the crag was in progress, much of the London clay has been wasted by denudation, 
ad and its Septaria mixed with the shells and bones during the later period of the forma- 
| tion of the crag. It is probable that the Septaria absorbed a still further quantity of 
phosphoric matter during their accumulation in the crag: it is possible, also, that 
| the peroxide of iron which pervades these pebbles and bones in the crag ‘may have 
% added to the phosphate when all the ingredients were in a semi-fluid state at the 
bottom of the sea. The Dean then referred to the discovery by Mr. Payne of beds 
| of pseudo-coprolites in the upper greensand of Farnham. Here sponges and other 
| organic bodies appear to have served as recipients of the phosphates; the Kimme- 
ridge clay of Shotover Hill contains abundant casts of the air-chambers of Ammo- 
_ hites filled with marl, and containing 20 or 30 per cent. of phosphate of lime. Since 
| all strata containing organic remains have more or less phosphoric compounds, these 
| must also be present in the soils preduced by their decomposition. Another large 
| lass of soils is produced from the decomposition of volcanic rocks and granite; in 
these phosphoric matter is also present, either combined with lime (apatite), or as 
erate of iron, and here its presence is unconnected with organized remains. 
In Spain the apatite forms an immense vein in ancient schists; and every specimen 
brought home by Dr. Daubeny has a radiated and stalactitic structure, showing that 
they were deposited from water, which must have taken it up previously from other 
ls, In conclusion, it was suggested that, since clay and marl and lime are em- 
ployed by Nature to absorb the phosphoric acid produced by the denampopition of 
r 5 


