2 H. H. NEWMAN. 



data. Accordingly in the winter of 1911 I journeyed from 

 Chicago to Texas and spent about a month in the armadillo 

 country collecting material, obtaining nearly two hundred 

 advanced polyembryonic sets together with the armor of the 

 mothers. 



A study of this material by my students and myself has brought 

 to light a situation so interesting, but withal so intricately com- 

 plex, that I almost despair of being able to render an intelligible 

 account of it. Yet I cannot but be impressed with the unique- 

 ness of the data and with the fact that it contains clews, afforded 

 by no other material, as to methods of attacking some of the 

 problems of the mechanics of hereditary transmission and of the 

 development of organic symmetry. 



In presenting the results of the study of the heredity of band 

 and scute anomalies I have found that the problems of heredity, 

 and that of the symmetrical distribution of these inherited 

 characters among the quadruplet embryos, are inseparably 

 parts of a larger problem that has to do with the mechanics 

 of organic symmetry. When, for example, it is found that a 

 bilateral anomaly in a mother is inherited unilaterally in the 

 various offspring and appears in reversed symmetrical relations 

 in twins, we have something more than a case of simple inherit- 

 ance. When again we find a unilateral anomaly in one pair 

 appearing bilaterally without reversed symmetry in the opposite 

 pair we see the problem in a more complex form. When, still 

 further, we note that an anomaly of a single scute in the mother 

 is inherited as such in some of the offspring and as a whole series 

 of anomalous scutes (a band anomaly) in others, we begin to 

 suspect that the problem is too intricate for any simple solution 

 and that only in certain of its aspects is it likely to yield to 

 analysis. Yet it is our duty to carry the analysis as far as our 

 data allows. 



That the circumstance of polyembryony vastly complicates 

 the already sufficiently complex problems of heredity can scarcely 

 be denied, but it is confidently hoped that the new relations 

 introduced by this unique type of development may throw 

 light from a different angle upon certain phases of heredity 

 that are now quite obscure. 



