2<; 



gested that a small quantity of sonic antibody siniiclmw 

 inhibited or destroyed a portion of the determiner for 

 pigmentation in the germ cell from which this family 

 sprung. This indeed points toward a possibility that unit 

 characters may arise from a partial destruction of larger 

 units; that a determiner for a unit character behaving 

 precisely in unit fashion may he a complex capable of 

 being shattered into a large number of independently be- 

 having characters. Small as the germ cell is and quanti- 

 tatively insignificant as the determiner for the skin and 

 hair pigment must be, the facts demand that this body 

 consist of many molecules arranged in definite structure, 

 each one destined for a somewhat definite ontogenetic 

 process leading to a definite somatic end. Thus the often 

 inherited specific color mark seems to indicate that a 

 color pattern once produced— no matter how intricate or 

 complex — will reproduce itself exactly until its deter- 

 miners are disturbed by unbalanced bodies or forces pre- 

 sented by fertilization or otherwise. 



The Shorthorns are a race of white cattle caught in the 

 making and preserved in the nascent state by a rigid selec- 

 tion. It is thus conceivable that mutations may arise 

 constantly, and that they may be progressive in char- 

 acter. Complications resulting in somatic effect are 

 legion, but nothing occurs in the germ cell giving rise to 

 new characters, splitting' up and combining others and 

 dropping out still others, that can not be analogously 

 pictured with the simple operations of the chemical 

 laboratory, and as ShuH's 2S illuminating "Simple Chem- 

 ical Device to Illustrate Mendelian Inheritance" seems 

 to indicate, the analogy is too constant and too far-reach- 

 ing to be cast aside as a mere pedagogical device. It may 

 indeed be a simple statement of facts of intra-gametic 

 and zygotic behavior and the analogy may no longer be 

 needed to picture the actual conditions. 



*>The Plant World, Vol. 12, pp. 145-153, July, 1909, and companion 

 paper, "The 'Presence and Absence' Hypothesis,'' The American Nat- 

 uralist, Vol. XLTTI, No. 511, pp. 410-419, July, 1909. 



