98 



Fossil Bones and Pseudo-Coprolites of the Crag. 



7. These pseudo-coprolites were very similar in appearance to 

 those described under a, bwt were obtained from a different 

 source. They were kindly presented to me by the late Mr. 

 Weddell, of Aldborouo:h, having been collected in the neighbour- 

 hood of Sutton, in Suffolk, 



Their densities were respectively 2- 7216 and 2-7891, whilst 

 their composition per cent, was as jfollows : — 



Water and organic matters . , 7*200 

 Chloride of sodium and sulphate of soda traces. 



Carbonate of lime 

 Carbonate of magnesia 

 Sulphate of lime 

 Phosphate of lime 

 Phosphate of magnesia 

 Perphosphate of iron 

 Phosphate of alumina 

 Oxide of manganese . 

 Peroxide of iron 

 Alumina . 



Fluoride of calcium . 

 Silicic acid and loss . 



Nitrogen, per cent. 



18'0]4 

 0-855 

 some. 

 51-018 

 traces. 

 8-902 

 2-700 

 0-057 



161 



593 



9-210 

 traces. 



5- 176 

 2-016 

 1-161 



45-815 

 some. 

 12-476 



6- 387 

 0-267 



2-688 

 14-804 



100- 



100- 



0-0289 



0*01989 



^. Three other specimens^ received at different times from other 

 parties^ contained, of — 



Per Cent, 



Earthy and other phosphates 

 Fluoride of calcium 

 Nitrogen , . 



64-056 79-545 67*176 

 0-311 2-554 2-768 



traces 0-0314 undetermined. 



III. True Coprolites. 



a. This coprolite was obtained from the lias of Lyme Regis, in 

 Dorsetshire, and was presented to me by my friend Mr. Barker, 

 of Budleigh Salterton. It was rather large, being above nine 

 ounces in weight, was of a grayish colour, and, when broken, 

 exhibited some traces of a crystalline structure. It was con- 

 siderably softer than any of the pseudo-coprolites above described, 

 and furnished a grayish-white powder. Many scales of different 

 extinct fishes and other organic remains were to be perceived on 

 the external surface ; the greater proportion of them appeared to 

 belong to a species of fish which is known to ichthyologists by 

 the name of Pholidopliorus limhatus. 



Its density was about 2 '644 or 2*700, and its composition per 

 cent, was as follows : — ■ 



