PRINCIPAL PHOSPHATE DEPOSITS. 



25 



III. England. — True coprolites or fossil excrements rich in 

 phosphate of lime in the form of more or less round lumps, 6 to> 

 20 cm. (2| to 8 inches) in diameter, are found in England in the 

 Lias marls, chiefly at Lyme Eegis. The interior is earthy like 

 hardened clay, but amongst these there can be readily distinguished 

 the teeth and the bones of the fishes and reptiles which served as 

 food to the saurians of the epoch such as the ichthyosaurus, the 

 pleiosaurus and the teleosaurus. Coprolites have been found at 

 the mouth of the Severn near Bristol. 



TABLE XIII.— ANALYSES OF LYME EEGIS COPROLITES. 

 (THOMPSON HERAPATH.) 



Water 



Organic matter 



Sodium chloride and sulphate 



Carbonate of lime . 



Carbonate of magnesia 



Sulphate of lime . 



Phosphate of lime . 



Phosphate of magnesia 



Phosphate of iron . 



Phosphate of alumina 



Ferric oxide . 



Alumina 



Silica, calcium fluoride, and loss 



Nitrogen 



Density 



I. 



Per cent. 



j 6-182 



traces 

 23-674 



1-077 

 60-769 I 



traces ' 



4-057 

 traces 



1-994 

 traces 



l-o52 



100-009 1 

 0-082 

 2-700 



11. 



Per cent, 

 2-976 

 2-001 



•28-121 

 0-423 

 0-026 



53-996 



6-182 

 1-276 



0-738 



100-000- 

 Undeter mined 

 2-799 



TABLE XIV.— ANALYSIS OF CAMBRIDGE COPROLITES. 



Moisture 

 Organic matter 

 Silica . 



Phosphate of lime 

 Carbonate of lime 



Per cent. 

 8-00 

 3-00 

 9-00 

 77-70 

 2-30 



100-00 



TABLE XV.— ANALYSIS OF SUFFOLK COPROLITES. 



Combined water . 



Sand oxide of iron 



Carbonate of lime 



Phosphate of lime 



Calcium fluoride sulphates and alkaline chlorides 



Per cent. 

 10-00 

 21-00 

 10-00 

 56-00 

 3-00 



100-00 



1 Totals to 99-305. 



2 Totals to 95-759. 



