Biological Institutions 85 



solve these problems the Institute is beginning a series of 

 studies upon man in the training school for the Feeble 

 Minded at Vineland, N. J., where records are being made of 

 the growth, behavior, and clinical history of some four hun- 

 dred inmates. In conjunction with this work post-mortem 

 examinations will help to explain human behavior in terms 

 of the structure of human tissues, both normal and diseased ; 

 while continued studies of the rat will, it is hoped, throw 

 further light upon the influence of an animal's surroundings 

 on its structure and activities. 



The effect of inbreeding in plants and animals is at present 

 but little understood. The general belief is that its results 

 are highly injurious to the offspring. In some species of 

 plants however we find special devices of nature to insure 

 self-fertilization, and the results of inbreeding various kinds 

 of domestic animals and plants are by no means uniform in 

 showing its harmful character. It has been stated that among 

 the Ptolemies and the Incas marriage of brother and sister 

 frequently occurred, while in ancient Persia the marriage of 

 parent and child was permitted. 



Hence the studies which Dr. King has been carrying on at 

 the Institute for several years upon the effect of continued 

 inbreeding on the growth, health, fertility and sex ratio of 

 animals, are of peculiar interest. As a result of these studies, 

 which are the most extensive hitherto made, Dr. King finds 

 that mating of brother and sister rats for thirty generations 

 produces no ill effect upon fertility and general health of the 

 offspring, provided the best animals are selected for breeding. 



One of the most important and interesting researches of the 

 Institute has been its studies on the refractive index of the 

 blood serum, which has been shown to differ, not only at 

 different ages, but also under differing conditions of health 

 and disease. Thus blood from persons afflicted with syphilis, 

 tuberculosis, cancer or Bright 's disease, has each its own 

 characteristic index; and the method, which is very simple, 

 gives promise of being a very valuable aid in the diagnosis 

 of disease. 



In the publication of journals the Institute performs one 

 of its greatest services to biology. The publication of such 

 journals, with their limited circulation, is always difficult 

 financially; but by systematizing and standardizing its 

 methods for several of them the Institute has been able to 

 reduce the expense of publication to a minimum, while at the 

 same time increasing their circulation and widening their 

 influence throughout the world. In 1919 nearly five thousand 

 copies of five journals were distributed to libraries and in- 

 dividuals in virtually every country in the world, at a net 



