84 



BIOLOGICAL LECTURES. 



Heredity. 



Repetitioti. 



A. Retrogressive to 

 present and past type. 



{a) Repetition of pa- 

 rental type. 



(b) Regression to pres- 

 ent race type usually in 

 several characters(= Vari- 

 ation from present pa7-en- 

 tal type). 



{c) Reversion to past 

 race type, usually in few 

 or single characters 

 (= Variation from pres- 

 ent race type). 

 Palinge7iic Variation. • 



Variation. 



A. Neutral both as re- 

 gards present or future 

 type. Including anom- 

 alies and abnormalities 

 which are purely individ- 

 ual phenomena not in the 

 path of evolution. 



B. Progressive to fu- 

 ture type. 



(a) Ontogenic varia- 

 tion from parental type 

 in one or more charac- 

 ters. 



(/') Ontogenic variation 

 from present race in sev- 

 eral characters (^a new 

 sub-type). 



(c) Phylogenic or con- 

 stant variation towards 

 future race type, in one 

 or more characters, con- 

 stituting a new 'Variety' 

 {= Repetition of parental 

 type). 

 Cenogenic Variixtion. 



The most profound gap in time is between 'palingenic vari- 

 ations,' springing from the past history of the individual, and 

 'cenogenic variations,' which have to do only with present and 

 future history. The former embraces more than reversion. 

 This table gives us only our first impression of this plane of 

 time so lightly regarded by Bateson, if indeed discrimination 

 is possible among data of the kind he has collected. The 

 distinctive import of human anatomy ^ is that a comparison of 

 the past and present habits of the race, or of the uses to which 

 bones and muscles have been and are now being put, opens a 

 possible analysis of variations both as regards their time of 

 origin and as regards their fitness to past, present, or future 

 uses; it is thus an inexhaustible mine for the philosophical 

 study of variation — of which only the upper levels have been 

 worked.^ Beside the human organism there is no other within 



1 R. Wiedersheim : P.au des Menschen als Zeugniss seiner Vergangenheit. 

 Freiburg, 1SS7. 



2 H. F. Osborn : Present Problems in Evolution and Heredity. The Cart- 

 wright Lectures. I. The Contemporary Evolution of Man, etc. Wm. Wood & 

 Co., New Vork, 1891. 



