INTKODUCTION. 



17 







Spec. 1. 



Spec. 2. 



Spec. 3. 



Spec. 4 



Phosphate of iron 



. 2FeA,3P05 



2.821 









" . magnesia 



. 3MgO,P03 



0.770 



2.099 



0.403 



0.98 



" " lime 



. 3CaO,P05 



69.685 



68.582 



83.835 



77.81 



" soda 



. 2NaO,P05 



1.415 



1.079 



1.413 





Sulphate of baryta 



. BaO,S03 



0.547 



1,728- 







" soda 



. NaO,S03 



1.083 



2.443 



1.437 



1.71 



" potassa 



. K0,S03 



0.587 



0.510 



0.442 



0.43 



" lime 



. CaO,S03 









0.60 



Silicate of lime . 



. 3CaO,Si03 



0.382 



0.732 



1.727 



2.23 



Carbonate of lime 



. CaO,COa 



9.315 



5.172 



7.212 



6.45 



Lime . 



. CaO 



6.605 



6.517 



1,284 



2.35 



Fluoride of calcium 



. CaPl 



0.716 



5.086 



0.099 



2.90 



Water 



. HO 



2.048 



1.971 



0.626 



2.10 



Organic matter 





5.682 



4.086 



2.538 



2.66 





101.656 



100.000 



101.016 



100.22^ 



Cuvier, in speaking of the remains of mammalia in the gypsum quarries of the 

 Paris basin observes, " on pent s'^tonner que dans une contr^e aussi ^tendue que 

 celle qu'occupent nos carrieres, at qui a plus de vingt lieues de Test a I'ouest on 

 n'ait presque trouve que des os d'animaux d'une seule famille, et que le petit 

 nombre d'esp^ces ^trangeres a cette famille principale, y soient d'une raret6 ex- 

 treme." The distinguished author infers from this a condition analogous to that 

 presented in our day by Australia. More recent researches, however, have shown 

 that in the single family alluded to, the Pachydermata, he included members really 

 belonging to one of the other Cuvierian families; for the Anoplotherium and Bir 

 chobune are now generally considered to have been true ruminating animals. 



With a single exception, all the species of extinct mammalia, which have yet 

 been obtained from Nebraska, belong to the TJngulata, and, as in the case of those 

 of the Paris basin above referred to, consist of Buminantia and Pachydermata. 



The great order of Ungulata, or hoofed mammalia, according to the idea originally 

 expressed by Cuvier, and confirmed by De Blainville, but more especially by Owen, 

 is divisible into two distinct sub-orders, the Paridigitata or even-toed ungulates, and 

 the Imparidigitata, or uneven-toed ungulates. 



The sub-order Paridigitata may be divided into the families Bumitianiia and 

 Ordinaria. 



The Buminantia are further divisible into sub-families as follows : — 



1. Those which are hornless, and have incisors and canines in both ^'aws; as 

 Anoplotherium, Macrauchenia, Dichobune, Chalicotherium, etc. 



2. Those which are hornless, and have canines and an incomplete series of in- 

 cisors or none at all, in the upper jaw; as Camelus, Auchenia, Mosclms, Dorcathe- 

 rium, etc. 



3. Those which have processes of the os frontis, or have antlers, in one or both 

 sexes, and have or have not upper canines, or have them in a rudimentary con- 

 dition, and which are without upper incisors ; as Cervus, Gameloepardalis, etc. 



* Proc. Acad. Nat. Sc, VI. 292. 



