Ga. XVI.] STRATA OF KYSOK IN SUFFOLK. 219 



sand has been found the first example of a fossil qiiadriimauous animal 

 discovered in Great Britain, namely, the teeth and rig. 230. 



part of a jaw, shown by Professor Owen to belong ^^^ 

 to a monkey of the genus Macacus (see fig. 230). ^^ 

 The mammiferous fossils, first met with in the Molar of monkey (J/acac^s). 

 same bed, were those of an opossum [Didel^yhys) (see fig. 231), and an 

 insectivorous bat (fig. 232), together with many teeth of fishes of the 

 shark family. Mr. Colchester in 1840 obtained Fig. 231. 



other mammalian rehcs from Kyson, among 

 which Professor Owen has recognized several 

 teeth of the genus Hyracotherium, and the ver- 

 tebrae of a large serpent, probably a Palceophis. 

 As the remains both of the Hyracotherium and 



^^ ,. „ - ;-i'jit Mo'ar tooth and part of jaw or 



Palceophis were afterwards met with in the Lon- opossum. From Kyson.* 

 don clay, as before remarked, these fossils con- 

 firmed the opinion previously entertained, that 

 the Kyson sand belongs to the Eocene period. 

 The Macacus, therefore, constitutes the first exam- 

 ple of any quadrumanous animal occurring in strata , , ^. ^. ^/^ 



^ "^ \ . (> n ^ Molars of insectivorous bats, 



so old as tlie Eocene, or m a spot so far from the twice nat. sko. 



, 1 , ;_^o -vr Ti. i. i.-i Ci. ii From Kyson, Suffolk. 



equator as Jat. 52 JN. it was not until after the 



year 1836 that the existence of any fossil quadrumana was brought to 



light. Since that period they have been discovered in France, India, and 



Brazil. 



Plastic or mottled clays and sands (0. 2, p. 208). — The clays called 

 plastic, which lie immediately below the London clay, received their 

 name originally in France from being often used in pottery. Beds of 

 the same age (the Woolwich and Reading series of Prestwich) are used 

 for the like purposes in England.f 



No formations can be more dissimilar on the whole in mineral char- 

 acter than the Eocene deposits of England and Paris ; those of our own 

 island being almost exclusively of mechanical origin, — accumulations of 

 mud, sand, and pebbles ; while in the neighborhood of Paris we find a 

 great succession of strata composed of limestones, some of them 

 siliceous, and of crystalline gypsum and siliceous sandstone, and 

 sometimes of pure flint used for millstones. Hence it is by no 

 means an easy task to institute an exact comparison between the 

 various members of the English and French series, and to settle 

 their respective ages. It is clear that, on the sites both of Paris and 

 London, a continual change was going on in the fauna and flora by 

 the coming in of new species and the dying out of others ; and 

 contemporaneous changes of geographical conditions were also in 

 progress in consequence of the rising and sinking of the land and 

 bottom of the sea. A particular subdivision, therefore, of time was 



* Anuals of Nat. Hist, vol. iv. K"o. 23, Nov. 1839. 

 f Prestwich, Water-bearing strata of London, 1851. 



