98 A GUIDE FOR THE STUDY OF ANIMALS 



D. Protective Habits and Powers 

 Materials. 



Specimens, charts, and books, showing habits of 

 invertebrates. 



Definitions. 



Regeneration, the power to grow new parts of the body 

 when parts have been lost or injured. 



Masking, the covering of an animal by some object or 

 organism so as to hide its identity. 



Nocturnal habits, the habit of hiding in the daytime and 

 coming out at night to feed. 



Terrifying attitudes, the protective attitudes assumed at 

 times by animals in order to ward off attack. 



Observations and questions. 



1. How are Sabella and Serpula protected } What ad- 

 vantages and disadvantages in this habit .' What changes 

 in structure are associated with this tube-dwelling habit .' 



2. What two protective habits has the earthworm } 

 Name some other animals that have similar habits. 



3. Describe the protective habits of the caddis fly larva ; 

 of the leaf-roller moth. What benefit to the hermit crab is 

 the colony of hydractinia growing on the snail shell which 

 it inhabits } Give other similar cases. 



4. Name as many cases of regeneration as you can. 



5. What peculiar habits has a puss-moth larva.'' a 

 dragon fly "i Give other examples. 



Summary. 



1. Name the various protective habits. 



2. State any advantages or disadvantages you can with 

 reference to these protective habits. 



