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STUDIES OF ANIMAL LIFE. 



li. Table of Appendages. 



1. Prepare a table similar to the model below. Fill out 

 the table with the proper entries in each column 

 for all the appendages in order, beginning with 

 the antennules. 



Number the appendages in order from the antennules. 

 Under "Special" include gills, paddle, palps, etc. 



Questions on the Table. 



a. How are the appendages homologous in structure? 



(" Homologous " means likeness in general 

 plan of structure.) 



b. Which appendages are the simplest in structure ? 



c. Which are the most highly specialized ? 



d. According to their uses how many groups of 



appendages are there ? 



e. According to their structure how many groups 



are there ? 

 Savigny formulated the law, "Uvery somite should 

 have a pair of appendages." 



(1) What is the evidence of the truth of this 

 law as shown in the crayfish ? 



(2) What evidence of its failure is there ? 



(3) Supposing it to be true, how many somites 

 are there in the body of the crayfish? 

 How many in the head? How many 



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