I'M W. JOHANNSEN 



This view is in its main points ol very ancient origin. The Hippo- 

 cratic school and a long series of authors including Cmaules Darwin 

 (Pangenesis) have promulgated such conceptions. Their purely mor- 

 phological nature can be emphasized in these words: Constituent Parts 

 of the Individual represented through special Partieles in the Sexual 

 Cells. Wf.ismann in his si)eculations as to »Germinal-selection» pro- 

 ceeded to absurdity in assuming independently living and competing 

 »Biophores) — as yet th(^ most ultra-morphological standpoint in 

 the lit<'rature of Genetics. Weismann continued to vindicate the parts 

 of the body as units in Variation and Heredity, even after full apprecia- 

 tion of Mendelism was attained. 



Of course parts were the most popular hereditary units of old: 

 the nose of your father, the eyes of your mother and the expressive 

 mouth of a grandfather may be elements of your natural inheritance. 

 But even Qualities have been regarded as units, especially those locali- 

 sed in special organs: The red colour of your grandmother's hair and 

 her delicate complexion may be inherited as well as musical endowment 

 and other probably brain-localised mental qualities. In such cases parts 

 and qualities might be regarded as inseparable characters (»Merkmale»), 

 i. e. as determined by the same »elements» in the zygote. We need not 

 enter the discussions of Aiustotle as to differences between homo- 

 geneous parts (tissues) and composite parts (hands, feet, face and so 

 on): some analogies between his views and the ideas of aggregated or 

 particulate inheritance in G Alton's publications may only be pointed 

 out here en passant. The profound accordance between Galton's 

 Stirp-theory, Weismann's primary Germplasm-teachings and Aristotle's 

 old original idea of continuity in Heredity (all in their turn rightly 

 discrediting the over and over alleged heredity of »acquired qualities») 

 has been mentioned by the present author on several occasions. Here 

 it is only of interest to emphasize the purely morphological nature of 

 these teachings. 



But besides a mori)h()l()gical analysis or »dissection» of organisms 

 in their ])arts there is a somewhat different view of analysing the na- 

 ture of an organism, viz. separating its more physiological features, 

 its different faculties or as we say »properties». A most conspicuous 

 example is furnished already in 1826 by Sageret when hybridizing two 

 melons, one with yellow and sweet pulp and another with white and 

 acid pulp. The progeny of this hybrid exhibited the four combinations: 

 yellow-sweet, yellow-acid, white-sweet and white-acid — an elegant 

 pre-Mendelian case. The said, morphologically speaking, homogeneous 



