StTMMARY. 193 



plants. The occasional discovery of bones and 

 teeth of reptiles, shows that the islands and conti- 

 nents were tenanted by oviparous quadrupeds.* 

 Of birds and mammalia not a vestige has been dis- 

 covered. 



* It is worthy of remark, that fossils and fragments of other rocks are 

 very rarely found in the white chalk. Pebbles of quartz and sandstone are 

 the only extraneous minerals of frequent occurrence. A solitary instance of 

 fragments of green chlorite schist, in chalk marl, near Lewes, was discovered 

 by myself some twenty-five years ago. My friend, Henry Carr, Esq. C E., 

 has recently found some water-worn pieces of fossil wood imbedded in while 

 chalk, from the cutting of the railway he is constructing between Epsom and 

 Croydon. This wood, in its mineralogical character and organic structure, is 

 unquestionably identical with the well-known fossil wood of the Portland 

 oolite, and I have no doubt is a portion of a mass that was drifted into the 

 bed of the cretaceous ocean. 



