THE OCEAN AND ITS INHABITANTS 17 



outlined in this book since their description would 

 require the use of too many technical terms. 



A family is composed of a number of different 

 animals that are all closely related. Each kind of 

 animal has two names — first a genus name which 

 always comes first and begins with a capital letter; 

 this is followed by a species name which always 

 begins with a small letter even if it is named for a 

 person or place. Closely related animals have the 

 same genus name but always different species names. 

 In a few cases there is a third or variety name which 

 follows the species name, but for most animals two 

 names are sufficient. 



The name of the animal is always followed by 

 the name of the man who first described it. For in- 

 stance, Asterias forbesi Desor is the common starfish 

 and was first described by Desor in 1848 and was 

 named in the honor of Forbes. Asterias tenera Stimp- 

 son is a related starfish that was described by Stimp- 

 son. The fact that they have the same genus name 

 shows that they are closely related. 



