THE NEARCTIC REGION 



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are represented by one species only, the well-known 

 Virginian opossum (Fig. 29), which is found with slight 

 modifications from the Southern States of North America 



Fig. 29. — The Virginian Opossum. 

 (Didelphys virginiana.) 



southwards over the greater part of South America. This 

 animal would, perhaps, judging merely by the present dis- 

 tribution of life, be considered to have intruded into the 

 Nearctic Region from South America, where alone members 

 of this family still survive ; but, on examining its past 



