Harris Hawthorne Wilder . 395 



obstetricians who had no opportunity of following the cases into later 

 years. Another cause of this lack of evidence is the great liability of the 

 death of at least one of the set before they have matured sufficiently to 

 show individual characters. We are thus forced to depend upon such data 

 as can be obtained concerning older children and adults, in which cases the 

 intra-uterine conditions are no longer obtainable, and it seems well-nigh 

 impossible Avith such observations as have been taken up to the present 

 time to obtain the three sets of coordinate data from any one case. This 

 has resulted in part from the difficulties in the way of obtaining data 

 requiring observations several years apart, but in great measure also from 

 the lack of theories to show what data are needed, and thus each observer 

 has obtained what seemed of interest to him. Although it is very evident 

 that a busy practitioner during the rounds of his daily and often nightly 

 visits has but little time for detailed observations beyond those called for 

 by the actual needs of the cases, yet learning is advanced by just such 

 data as those which he has the opportunity to collect, and it is by the 

 compilation of facts like these that most important generalizations may 

 be ultimately obtained. Any facts obtained and communicated to the 

 writer or to any one else at work upon the theoretical side of the subject 

 will further the advance of general knowledge in this field. 



So far as I have been able to learn there is, as in the case of twins, a 

 general belief that triplets and quadruplets ought to look very much 

 alike, but the data obtained from the placental conditions certainly sug- 

 gest that cases of fraternal components may also occur, either with or 

 without the combination of duplicate components in the same set. One 

 sees occasionally photographs of duplicate twins or even quadruplets 

 employed for the purpose of advertising some infant's food or similar 

 goods, but, although the probabilities are that they are authentic, there 

 are numerous possibilities of deception known to modern photography, 

 even to the repetition of a single person upon one and the' same plate, 

 thus rendering data from these sources a little too unreliable for use in 

 this place. I have obtained, however, a genuine case of triplets, the com- 

 ponents of which are all duplicates of one another. A photograjDh was 

 taken of these at the age of eighteen and exhibits a remarkable degree of 

 resemblance. In early life the physical identity of these triplets must 

 have been complete, as the following extract will show, taken from a letter 

 concerning them written by a lady who, when a young girl, knew the 

 triplets as children. " I have seen twins that looked very much alike, 

 but I could see a difference when they were together. I could not see 

 any difference in these triplets when they stood in a row before me, and I 

 never saw any one .else who could, except their mother. She said she 



