Animals Before Man 



young king crabs with trilobites, for it is a 

 general rule that in their very young or em- 

 bryonic stages animals show their affinity with 

 those of simpler structure and lower in the 

 scale of life. The three lobes which suggested 



Larva of a trilobite. 



Dalmania limulurus. Larva of a king crab. 



the name trilobite are marked by two more or 

 less pronounced grooves running lengthwise of 

 the body, dividing it into three portions, while 

 the head, body, and tail also divide trilobites 



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