456 



PROGRESSIVE DISCOVERY OF VERTEBRATA fCm XXVII. 



may be useful in warning us not to assume too hastily that the point 

 which our retrospect may have reached at the present moment can be 

 regarded as fixing the date of the first introduction of any one class of 

 beings upon the earth. 



Dates of the Discovery of different Classes of Fossil Vertebrata ; show- 

 ing the gradual Progress made in tracing them to Hocks of higher 

 Antiquity. 





Year. 

 [" 1198. 



Mammalia. - 



1818. 

 k 1847. 



Aves. 



' 1782. 

 [ 1839. 



Reptilia. 



1710. 



1844. 



[ 1852. 



Pisces. 



' 1709. 

 1793. 



1828. 

 _ 1840. 



Formations. 

 Middle Eocene (or B. i. p. 222). 



Lower Oolite. 

 Upper Trias. 



Middle Eocene (orB. i. p. 222). 



Lower Eocene. 



Permian (or Zechstein). 

 Carboniferous. 

 Upper Devonian. 



Permian (or Kupfer-schiefer). 

 Carboniferous (Mountain Lime- 

 stone). 

 Devonian. 

 Upper Silurian. 



Geographical Localities. 

 Paris (Gypsum of Mont- 



martre). 1 

 Stonesfield. 2 

 Stuttgardt. 3 

 Paris (Gypsum Mont- 



martre).* 

 London (Sheppey Clay). 5 



Thuringia. 6 



Saarbruck, near Treves. 7 



Elgin. 8 



Thuringia. 9 

 Glasgow. 10 



Caithness. 11 

 Ludlow. 13 



1 Cuvier (George). Bulletin Soc. Philom. xx. Scattered bones were found in 

 the gypsum some years before ; but they were determined osteologically, and 

 their true geological position was assigned to them in this memoir. 



2 In 1818, Cuvier, visiting the Museum of Oxford, decided on the mammalian 

 character of a jaw from Stonesfield. See also above, p. 311. 



3 Plieninger, Prof. See above, p. 340. 



* M. Darcet discovered, and Lamanon figured, as a fossil bird, some remains 

 from Montmartre, afterwards recognized as such by Cuvier (Ossemens Foss., Art. 

 " Oiseaux"). 



8 Owen, Prof., Geol. Trans. 2d Ser. vol. vi. p. 203, 1839. The fossil bird dis- 

 covered in the same year in the slates of Glaris in the Alps, and at first referred 

 to the chalk, is now supposed to belong to the Kumniulitic beds, and may there- 

 fore be of newer date than the Sheppey Clay. 



6 The fossil monitor of Thuringia (Protorosaurus Speneri, V. Meyer) was figured 

 by Spener, of Berlin, in 1810. (Miscel. Berlin.) 



7 See above, p. 397. 



8 See above, p. 412. 



8 Memorabilia Saxoniae Subterr, Leipsic, 1709. 



10 History of Rutherglen, by Rev. David Ure, 1793. 



11 Sedgwick and Murchison, GeoL Trans. 2d Ser. vol. iii. p. 141, 1828. 



12 Sir R. Murchison. See above, p. 431. 



Obs. The evidence derived from footprints, though often to be relied on, is 

 omitted in the above table, as being less exact than that founded on bones and 

 teeth. 



How many living writers are there who, before the year 1844, gener- 

 alized fearlessly on the non-existence of reptiles before the Permian era ! 

 Yet, in the course of ten years, they have lived to see the earliest known 

 date of the creation of reptiles earned back successively, first to the Car- 

 boniferous, and then to the Upper Devonian periods. Before the year 

 1818, it was the popular belief that the Palseotherium of the Paris gyp- 

 sum and its associates were the first warm-blooded quadrupeds that ever 



