334 



The Journal of Heredity 



m^ age of the mother. "We have, 

 however, distinctly guarded ourselves 

 from any expression of the source of 

 the inferiority of the first-born till the 

 data, slowly accumulating, suffices to 

 determine how much the first-born pays 

 for the juvenility and how much for 

 the inexperience of its parents. 



" It will be seen from the totality of 

 the above results that physically, in 

 the early months of life, the first- or 

 earlier-born babies are inferior to any 

 babies before at least the seventh or 

 eighth. We have now to ask whether 

 this inferiority persists to later life, and 

 whether it shows itself also in congenital 

 defects." 



CONGENITAL DEFECTS 



Idiocy or imbecility is the first 

 defect considered.- No matter in what 

 way the data are analyzed, it appears 

 that there is a distinct bias against the 

 first-born. 



Weeks' American data on ei)ilcpsy 

 are next analyzed. "We must, I think, 

 conclude by recognizing that, while 

 there is a weighting of the elder-born 

 even in ejjilepsy, this is due to a selec- 

 tion of families rather than to a selec- 

 tion of the elder-born in each individual 

 family." In other words, the statistical 

 observation that there are more first- 

 born than later-born epileptics in an 

 asylum is of no significance except 

 when a large po]julation is considered — 

 it does not mean that in any given 

 famil)' the first-born is likely to be 

 inferior in this respect to his or her 

 successors. 



The data for insanit}' are said not to 

 have been available for such full 

 analysis as were data of other defects. 

 They appear to show that there is a 

 weighting of the elder-born in the case 

 of insanity, but they do not furnish 

 grounds for saying that this may not 

 be due merely to the fact that the 

 subjects observed come of defective 

 stocks. 



Pedigrees of 952 albinos of Euroi)ean 

 race are next examined. There is 

 marked excess of albinos among the 

 first-V)orn: 241 cases instead of the 216 



expected by the theory of probability; 

 the second-born have no excess and 

 the last-born seem to show a slight 

 defect. "I think there cannot be the 

 least doubt," Pearson concludes, "of 

 a quite significant weighting of the 

 first-born in the matter of albinism." 



Criminality, on the basis of Dr. 

 Goring's figures, seems equally to be a 

 l^rcrogative of the elder members of the 

 family. When expected and observed 

 distribution of criminals in families of 

 each size is computed, "the actually 

 observed first- and second-born crim- 

 inals amount together to 717 as against 

 557 which would be anticipated if the 

 tendency to crime were divided equally 

 among all members. There is a defect 

 of both intermediates and of last-born 

 criminals. The general bias against 

 the elder-born appears amjjly substan- 

 tiated on these data." 



Statistics for the tub^Tculous are 

 next considered, in a much more refined 

 way than was attempted when the 

 first study was made. Even when each 

 family is considered individually, it is 

 found that there is a heavy preponder- 

 ance of tuberculosis in the case of the 

 first-borns, and a defect in the case of 

 the late-borns. 



Pedigrees of fifty families with con- 

 genital cataract are finally taken up, and 

 here too "the less robust members of a 

 tainted stock — and such are the first- 

 born — ap]:>ear more likely to be 

 affected." 



CRITICISMS NOT AALII) 



In conclusion, Pearson holds "that 

 the criticisms raised against the handi- 

 capping of the first-born are not valid. 

 The first-born is very significantly 

 handicap])ed, and this statistical result 

 will coincide with a good deal of ])crsonal 

 and individual ex])erience." 



At the risk of tiresome rejx'tition, it 

 must one more be pointed ovit that 

 when the ])roblem is demonstrated by 

 statistics, the handicap of the first-born 

 might be of two kinds: it might be that 

 the first-born in each family is actually 

 inferior to the later-born, or it might be 

 that the first-borns, as a whole, in the 



2 The type of feeblemindedness known as Mongolian is excluded from consideration, because it 

 is already known to be associated with late births in large families. It is ordinarily attributed to 

 "uterine exhaustion" of the mother. 



