DISTRIBUTION OF INHERITABLE TRAITS 193 



Block Island, comprising about 10 square miles, lies 

 about 40 miles both from Newport, Rhode Island, and from 

 Montauk Point. There are some fine old family names 

 including Ball, Cobb, Dodge, Hall and Littlefield, which 

 constitute a large part of the population of 1,500 souls. 

 The limited area has, however, led those branches of the 

 family who remain on the island to intermarry closely, as 



DO 6 DO oAo OD D D 



„D-6 6 ~op oi q6 



Dodqe Dodge Ball Dod^e 



tip 5o iiroiiiip ho6 



I Dodge 



iiioii irOOii""(!x] DiO do 



" ' T1-J-- Dodge Dodge 



Dodge Dodge 



^ Qq6o OD 



Ball Ball Dodge .DoageBaiU- Ball Dodge 



Fig. 171. — Portion of pedigree of the Ball family of Block Island showing 

 frequency of marriage with Dodge and with Ball; a consequence of Hmited 

 marriage selection in a small island. 



illustrated in Fig. 171 based on Ball (1891). The result 

 has not been good. There are famihes in which all the 

 children are mentally deficient and many marriages that 

 are childless. 



As we go south along the Atlantic coast, beaches or 

 ^' banks" replace offshore islands. When they are so far 

 from the mainland, as at Pamlico Sound, as to make inter- 

 communication difficult, consanguineous marriages occur in 

 extraordinary frequency. A wide-spread trait that may 

 be ascribed to such inbreeding is suspicion and mental 

 dullness; and a relative high frequency of insanity. Even 



