252 BIOLOGY: GENERAL AND MEDICAL 



-this be so, then we can picture that in the process of reduction and 

 casting out of biophoric material in the development both of the 

 oocyte and of the spermatocyte, while there are delivered to the 

 ovum molecules of living matter which in direct descent have been 

 derived from one parent only, those molecules may convey to the ovum 

 constitution and properties which have been derived from both 

 parents. In this way, without any increase in the number of 

 determinants or ids, by this chemical modification of biophores, a 

 constant number of such biophoric molecules may become the 

 bearers of properties derived from a long series of ancestors. 



"We purposely do not here consider all the different types of 

 inheritance, for this is not a full treatise upon the subject. We 

 have taken up forms that are sufficiently wide apart to show that 

 this biophoric theory is capable of elucidating their occurrence. 



"It appears to us to have the great advantage of explaining how 

 hereditary characters may be conveyed through a relatively small 

 number of molecules of highly complex organization; how those 

 molecules can in the course of amphimixis undergo modification 

 through interaction; how they can become modified through the 

 action both of amphimixis and of environment; how similarly they 

 may undergo retrogressive changes and lose certain properties 

 under the same influences. 



"With reference to the action of environment on the germinal 

 biophores it is still necessary that something be said, but our 

 treatment of the subject of amphimixis will not be complete with- 

 out reference to the remarkable reduction process that precedes 

 fertilization. The mode of that reduction we have already 

 described. We have seen that in the process of the maturation 

 of the ovum, three-quarters of the chromatin present in the 

 penultimate stage of the process is cast out (three polar bodies), 

 one-quarter only being retained, and that similarly the sperma- 

 tozoon is developed from one-quarter of the nuclear matter of the 

 primary spermatocyte. 



"As shown by the abundant recent studies on Mendelism, the 

 results of this reduction may be very remarkable; certain proper- 

 ties may at a single conjunction be thrown out so completely that 

 they do not reappear in subsequent generations. 



" During the very first process of reduction in a hybrid a property 

 or properties derived from the one parent may thus be thrown 

 out; and yet when the parents had differed in several particulars, 

 at this same moment properties derived from the other parent 

 may likewise disappear. And as in such hybridization there may 

 be as many as a score of properties in which the two parents had 

 been contrasted size, color of flower, position of flowers, shape of 

 leaf, hairiness of leaves, shape of seed, etc., the process of 

 sorting prior to this casting out, if we regard these qualities as 

 conveyed by distinct ids or determinants, is beyond conception. 

 It demands so exact a localization in each chromosome of the 

 particular determinants, and at the same time so precise a dis- 

 tribution of the determinants for the various properties, that by no 

 possible means have we been able to visualize what is supposed to 

 happen. By the biophoric concept this casting-out process is, 



