INTRODUCTION. 7 



Drinkwater's terms are found in most of the text books, but it will 

 be seen from the citations given that their definition is rather vague. 

 Moreover, the radiographs show that not the fingers and toes as a 

 whole, but quite definite phalanges, are shortened. It is therefore 

 preferable to abandon these inadequate terms and use the precise 

 name " brachyphalangy " earlier proposed by Pfitzner. In our case it 

 is quite necessary to use the latter term because the malformation can 

 not be characterized by one or the other name as outlined by Drink- 

 water's definition, both degrees of shortening occurring within the 

 family studied. The term brachyphalangy has furthermore the advan- 

 tage of covering all the numerous types of analogous malformations 

 to which neither of the two terms of Drinkwater can justly be applied. 



During the course of the investigation the authors have become 

 indebted to several persons who have rendered valuable assistance in 

 providing radiographs and photographs, and our most sincere thanks 

 are tendered to Dr. Heyerdahl, of Rigshospitalets Rontgenavdeling, 

 Christiania; Dr. P. F. Hoist, of Rigshospitalet, Christiania; Dr. Olav 

 Hanssen, Bergens kommunale sygehus; Dr. Paus, Lindboe's Klinik, 

 Christiania; Dr. Wood, of the Cancer Laboratory, Columbia Univer- 

 sity, New York; Mr. A. F. Huettner, New York; and Dr. Hektoen, of 

 the John McCormick Institute, Chicago. We are similarly indebted 

 to the medical students Kreyberg, Waaler, and Lie. 



One of the authors, Mohr, who carried out the composition of this 

 paper while working in the laboratory of Dr. T. H. Morgan, at Colum- 

 bia University, wishes to express his most sincere thanks to Dr. Morgan 

 for his help and encouragement in many ways as well as for the hos- 

 pitality and facilities enjoyed during the work. He also takes the 

 opportunity of acknowledging his large indebtedness to Dr. Bridges 

 and Dr. Sturtevant for then- assistance. Dr. Sturtevant, in addition, 

 took the burden of correcting the English text, a kindness for which 

 the authors feel specially and sincerely thankful. 



The collection of radiographs and photographs of members of the 

 family, often living in distant communities, was made possible through 

 a grant awarded by Nansenfondet, Christiania. An opportunity of 

 including some of the American members of the family in the present 

 investigation was obtained when one of the authors obtained a fellow- 

 ship of the American-Scandinavian Foundation. 



