QUESTIONS. 357 



158. What is the part generally called the " tail," and what is the so- 

 called " head ? " 



159. What are the " antennae," and how many are there in the Lobster 

 and in Crustacea generally ? 



160. What are "foot-jaws," and why are they so called? 



161. What are " chelae ? " 



• 162. Of what nature are the appendages of the abdomen in the Lobster ? 



163. What Is the last segment of the abdomen called ? 



164. Describe the gills of the Lobster. Where are they placed ? 



165. Of what nature is the abdomen of the Hermit-crabs ? 



166. How are the Crabs distinguished from the Lobsters ? 



167. By what character does the young Crab approach the Lobster ? 



168. Give an example of the Jsopoda ? 



169. What is the character of the appendages of the mouth in the King- 

 Crabs ? 



170. What is the structure of a Trilobite ? 



171. What is the nature of the sheU of the Ostracode Crustaceans ? 



172. What change do the Cirripedes undergo in passing from the larval 

 to the adult condition ? 



173. What are the two types of the Cirripedes ? Give examples. 



174. Give the general characters of the Arachnida? 



175. What is the structure of the mandibles of the Spiders ? Of the 

 Scorpions ? 



176. To what do the mandibles of the Arachnida correspond ? 



177. Of what nature are the breathing-organs of the Arachnida? 



178. What is the structure of iracAece .? Of pulmonary sacs ? 



179. What are the organs of vision in the Arachnida ? 



180. What are the habits of the Mites ? Give examples. 



181. By what structure do the Scorpions inflict wounds ? 



182. What is the condition of the abdomen in Scorpions ? In Spiders ? 



183. By means of what organs do the Spiders spin webs? 



184. What are the general characters of the Myriapoda I 



185. What is the general condition of the young Myriapod? 



186. What are the distinctions between the Centipedes and Millipedes ? 

 137. What is the number of legs in Pauropus ? 



188. What are the general characters of Insects ? 



189. What organs are carried by the head in Insects ? 



190. How many segments form the thorax, and what appendages do they 

 always carry ? What appendages do they sometimes carry ? 



191. What are "nervures?" 



192. How many rings generally go to the abdomen of Insects ? What 

 appendages (if any) do these support ? 



193. What are the chief modifications in the organs of the mouth in 

 Insects ? 



1 94. Describe the digestive system of an Insect ? 



195. How is the circulation carried on ? 



196. Of what nature are the breathing-organs ? 



197. Of what nature are the eyes in Insects ? 



198. What is understood by the " metamorphosis " of an Insect ? ' 



199. What are the chief differences in the metamorphoses of Insects ? 



200. What peculiarity distinguishes the adult state of Insects which 

 undergo no metamorphosis ? 



201. What is understood by the terms "larva," "pupa," and "imago?" 



202. What is a " chrysalis ? " A " cocoon ? " 



