40 HEREDITY AND EUGENICS 



conditions in man, as well as concerning the effec- 

 tive environmental factors which are involved in 

 producing racial differences in stature. 



A condition which bears some resemblances to 

 achondroplasia, but was probably of a different 

 character, appeared in a flock of sheep in i 791 (Hum- 

 phreys, 1 813). The so-called Ancon sheep originated 

 from a single ram in the flock of a farmer in Massa- 

 chusetts, near Boston. This ram had short, bandy 

 legs and a short back. The character was evidently 

 a simple Mendelian recessive, and had probably been 

 carried in the stock for some time before it was brought 

 out b}' inbreeding. The breed seems to have attained 

 some popularity because they could not jump fences ; 

 but their crooked forelegs, loose joints, and flabby 

 subscapular muscles made them difficult to drive to 

 market, their carcasses were smaller, and they became 

 extinct some time after 181 3. This is an excellent 

 example of man's power over variations in domestic 

 animals, first to multiply them and afterwards to 

 bring about their extinction when the}^ were found 

 less serviceable. 



A somewhat different account of the origin of this 

 breed was given b}^ Timothy Dwight (1822, vol. iii., 

 p. 134). Hesays that about i 798, in Mendon township 

 (Mass.), about eighteen miles south-east of Worcester, 

 *' an ewe belonging to one of the farmers had twins, 

 which he observed to differ in their structure from any 

 other sheep in this part of the countr}^." The twins 

 are said to have been of different sex, and to have been 

 bred together to produce the new race. Dwight stated 

 that their bodies were thicker and more clumsy, 

 they were more gentle, and have since multiplied to 

 many thousands; when crossed with other breeds, 

 they always resembled entirely either the sire or the 

 dam. 



The dachshund among dogs appears to have re- 



