GENETICS: H. CUSHING 
621 
cise data as to the occurrence of heritable variations and their accumu- 
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can hardly fail to have influence on the conception of the hereditary 
constitution or genotype as a fixed thing, changing only discontinu- 
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Variations in Bacteria, /. Inject. Diseases, 6, 90-97. 
HEREDITARY ANCHYLOSIS OF THE PROXIMAL PHALAN- 
GEAL JOINTS (SYMPHALANGISM) 
By Harvey Gushing 
HARVARD MEDICAL SCHOOL AND PETER BENT BRIGHAM HOSPITAL, BOSTON 
Presented to the Academy, October 30, 1 91 5 
There are many recognized forms of congenital malformations of the 
hands and feet. Walker in 1901 first described the type of deformity 
which is made the subject of this study, and showed that the condition 
had been transmitted through five generations, though the number of 
his recorded cases w^as too small to justify a definite conclusion on a 
Mendelian basis. Farabee in 1905, and Drinkwater in 1908, showed 
that another type of deformity of the hands, known as brachydactylism, 
was a dominant unit-character, transmitted in accordance with the 
Mendelian law. 
The lesion in the condition under discussion consists of a congenital 
anchylosis, due apparently to the failure of formation of the joint between 
