No. 501] 



XOTES AND LITERATURE 



615 



more than yellow females. According to our assumption this 

 should be the case, since yellow males transmit yellow to all off- 

 spring, while yellow females transmit yellow only to their male 

 offspring. 



That one factor of the eye color in canaries is allelomorphic to 

 the female sex element is also clearly indicated by Noorduijn's 

 results. He gives only a meager portion of his experimental 

 results on this point, so that the phenomena can not be explained 

 here. There is enough to indicate that the ease involves at least 

 three independent Men< Id i;m factors, one of which is correlated 

 with yellow coat color, and hence allelomorphic to the sex ele- 



W. J. Spillman. 



HUMAN ANATOMY 

 Sexual and Family Variation in Centers of Ossification. — Dr. J. 



W. Pryor, professor of anatomy and physiology at the State 

 University, Lexington, Kentucky, for several years has been 

 carrying on an investigation of the ossification of the bones of 

 the human carpus, by means of X-ray photographs. He has 

 made a study of over 550 hands, of which 266 were those of girls 

 and 288 those of boys. In numerous instances he has examined 

 the hands of the same individual at different periods, and has 

 also made a study of the ossification of the bones in children of 

 one family compared with those of other families. In a recent 

 article in the Bulletin of the State University, Lexington, Ken- 

 tucky, April, 1908, he has summed up some of the conclusions 

 arrived at in previous publications, and has brought forth new 

 material in confirmation of his more important generalizations. 

 He finds centers of ossification appear earlier and develop faster 

 in the bones of the female than in those of the male, and that 

 this difference is measurable in infancy by days, in early child- 

 hood by months, and later by years. The bones of the first child 

 will, as a rule, ossify sooner than those of subsequent children of 

 the same parents. There is considerable difference in the chil- 

 dren of different families in the period when centers of ossifi- 

 cation appear, but within a given family there is, as a rule, con- 

 siderable similarity. Variation in the ossification of bones is an 

 heritable trait. The studies of Professor Pryor enable him to 

 give a more accurate table than has hitherto existed of the period 

 when the centers of ossification appear in the carpal bones. The 



