438 Duplicate Twins and Double Monsters 



could ever exist in any other two people" (p. 435). Altliough these 

 tracings and the brief statements accompanying them gave a general 

 idea of the remarkable correspondences in such cases, they formed 

 scarcely more than an announcement of an interesting line of investi- 

 gation, and it is to supplement this that the facts presented in the 

 present paper are given. In this the first consideration will naturally 

 be bestowed upon the epidermic markings, although in order to make the 

 investigation as complete as possible, I have thought it advisable to add 

 anthropometric data and other matters of interest. 



The material at my disposal for use in the present investigation in- 

 cludes some data, at least, and in nearly all cases sets of prints, of 16 

 sets of twins and two sets of triplets, as shown in the following table: 



The sets are designated by Eoman numerals and the individuals of a 

 set by the letters x and y (and z), both sets of designations correspond- 

 ing to names and numbers as listed in my private collection. In the 

 determinations of the physical appearance I have designated with an 

 asterisk all cases that I have had the opportunity of observing person- 

 ally. In the other cases I have depended upon the descriptions of others, 

 usually the collectors of the prints. In the most of the " unlike " cases 

 the difference is so marked as to leave no doubt as to the determination, 

 notably in the case of No. VIII, where the two individuals, although 

 both of the same sex, are strikingly unlike in every way, while a third 

 sister, two years 3'ounger than they, resembles one of them almost 

 enough to pass for her duplicate. Nos. VII and X are the only ones 

 that occasioned any hesitation and in this I was prejudiced by state- 

 ments of the families, who, in both cases, consider that the twins are 

 very much alike, but the differences seen by unprejudiced observers are 

 sufficient to class No. X positively, and No. VII probably, in the fra- 

 ternal class. 



I may here take the oj^portunity of thanking the numerous persons 

 Avho have aided me in this investigation; several of my present and for- 

 mer pupils, to whom I am indebted for Numbers I, II, III, IV, XVI, 

 and XVIII; my assistant, Miss Inez Whipple, who obtained the data 

 of No. VII and the photograph of No. XVIII; Miss L. I. Mattoon, 

 M'ho collected Nos. XIII and XIV; Miss C. F. Eobinson, who collected 

 the valuable set of triplets. No. XII ; and Dr. R. H. Johnson, of the 

 University of Wisconsin, who sent me No. V. I wish also to thank 

 Prof. Edward Hitchcock, Dean of Amherst College and Director of the 

 Gymnasium of that place, and Miss Senda Berenson, Director of the 

 Gymnasium of Smith College, who have presented me with the anthro- 

 pometric measurements made use of here. My thanks also would not 



