Fossil Bones and Pseiulo-Coprolites of the Crag. 



103 



cent. ; the average proportion, however, being about 32 or 33 per 

 cent.:* consequently, leaving the nitrogen and other constituents 

 out of consideration, powdered coprolites may be said to possess 

 at least an equal agricultural value with the bones of animals. 



3rd. That the proportion of fluoride of calcium present in these 

 phosphorites varies exceedingly, sometimes occurring only in 

 traces, whereas at others it amounts to as much as 4» 1 per cent. 



4th. That the fossil bones of the crag are generally richer in 

 phosphoric acid than normal bones, and, therefore, are equally 

 well, if not better, adapted than them for the fertilization of land.f 



5th. That the proportion of fluorine which is met with in the 

 bones of extinct animals and fishes is considerably greater than 

 that in those of any species now in existence.^ 



Fossil bones, as an average, contain, according to my experi- 

 ments, 3*912 percent, of fluoride of calcium, whereas the bones 

 of species of animals now in existence, according to Berzelius, 

 contain it only in very small quantity, certainly not more than 1 

 per cent. 



6th. That the proportion of phosphates and fluoride of calcium 

 is greater in the hard and solid bones than in those which possess 

 a more open and spongy texture. 



* According to the results of previous experimenters these nodules contain — 

 From 24 to 25 per cent, of phosphoric acid (Mr. Way). 

 25 to 26 (Dr. Gilbert). 



22-2 to 28-74 (Mr. Nesbitt). 



f The follomng table contains the results of the most recent experiments of Prof. 

 Marchand, aud shows the proportiou of phosphoric acid and phosphates which is met 

 with in the bones of diiferent animals : — 



Bones in their normal state. 

 \ i Ox Bones. Sheep. Human. 



Phosphate^on:™ ^ . . I ^3.3„ , ^ f . ^^^^ 



Phosphate of magnesia. . ) ^ 1 2S-04 ) -, f 29-80 ^ , .^o f 23-30 



(3Mgo,po^). ; -^'^^ j I ^"^^J [ J 



The proportion in the bones, after being deprived of organic matter, was as follows : — 



Ox Bones. Sheep. Human. 



Phosphate of lime . . 1 83-07 1 = PO^ f 84-39 1 =P05f 85-73 1 =P05 

 Phosphate of magnesia . | 2-98 j 39-96 \ 2'15 J 40-12 { 1-74 j 40-52 



No analyses of the bones of cetacean iinimals have been published. 



In the bones which he examined, Middleton found a much larger amount of 



luorine. The proportion of fluoride of calcium per cent, was as fol' 



Colossochylus atlas of the Sewalic Hills 

 Fossil ruminant of the Sev/alic . 

 Fossil horse of ditto .... 

 Fossil camel of ditto 

 Fossil alligator of ditto . . 

 Iguanodon of the Wealden, 



( Greek skull (2000 years old) 

 Not fossilized I Skull of an Egyptian mummy 



ows : — ■ 



11*68 



10- 65 



11- 24 

 11-16 



4- 85 

 11-51 



5- 04 

 2-34 



Recent skull , . . .1-88 to 1-99 



