QUESTIONS. 339 



of the time occupied in their formation ? What is said of the forma- 

 tion of limestone rocks from shells ? 



107. What is said of the foraminifera ? What of the agency of 

 minute animals, in comparison with large ones, in forming the earth's 

 crust ? What is stated about the nummulites ? What is oaze, and 

 what is said of it ? 



158. Of what are the limestone strata quarried near Paris com- 

 posed? What did Ehrenberg find in chalk? Mention the observa- 

 tions of Soldani. What is said of silicious shells ? What of the 

 white clay about Richmond ? 



159. What of the tripoli of Germany? What is supposed to be the 

 origin of the flint-stones found in chalk ? What is said of the extent 

 of the agency of silicious animalcules and plants in forming rocks ? 

 What is the nature of diatoms ? What is said of the formation of 

 seas, lakes, and rivers ? What is said of plan in the construction of 

 the earth ? 



160. What is said of life in the different ages of the earth ? What 

 of making out the order of succession in the rocks by the life-record ? 



161. What is said of the resemblances of present living forms to 

 those of the past ? What is the nature of the evidence from the life- 

 record as to the relative ages of the strata ? What is said of the cor- 

 respondence of the evidence in different countries ? Illustrate this 

 by reference to the coal formation. 



162. What are fossils ? What is the origin of the term ? In what 

 different degrees are fossils preserved ? What is said of petrified fos- 

 sils? What of casts of living substances made by some mineral? 

 Why may coal, strictly speaking, be considered a fossil ? State what 

 is said of the preservability of different fossils. 



163. Give in full what is said of the abundance of fossils. Explain 

 the principles on which Cuvier and others have investigated fossils. 



164. Show how these principles are applied by most people to a 

 limited extent. How is skill acquired in applying them ? What is 

 said of their application to vegetables ? What is the derivation of the 

 word Palaeontology? What is said of the general plan of living 

 structures ? 



165. What are the Acrogens, and why are they so named ? What 

 are the Gymnogens, and what is the derivation of their name ? What 

 purpose have these and the Acrogens served? 



167. What relations had the Acrogens and Gymnogens to animal 

 life? 



169. What are the Endogens ? What is their chief purpose ? 



170. What is meant by a geological, and what by a zoological 

 agency ? Explain the meaning of the term Endogens. How does 

 the mode of growth in an Exogen differ from that of an Endogen ? 



