271 



the inside. It represents the sum of external conditions and influences at the 

 present moment, and is proclaimed all-suflicient for building up organisms out 

 of isotropic corpuscles. Previous conditions are not, indeed, quite ignored, for 

 they have resulted in special molecular constitutions called germs, and these dis- 

 play molecular activities known as metabolism, growth and division. The long 

 past can bring forth only a molecular basis; a few hours of the present can sup- 

 ply all, or nearly all, the determinations of the most complex organism. Im- 

 potent past ; prepotent present. We have no longer any use for the 'Ahnengal- 

 lerie' of phylogeny. Heredity does not explain itself or anything else, and it 

 detracts from the omnipotence and universality of molecular epigenetics. We 

 are no better off for knowing that we have eyes because our ancestors had eyes. 

 If our eyes resemble theirs it is not on account of geneological connection, but 

 because the molecular germinal basis is developed under similar conditions. 

 The reason this basis becomes an eye rather than an ear or some other organ is 

 wholly due to its position and surroundings, not to any inherent predetermina- 

 tions. If the material for the eye and the ear could be interchanged in the 

 molecular germ, that which in one place would become eye would in the other 

 place become ear, and vice versa.^' 



16. In what characters does the same species in the neighboring lakes difien 

 and in what respects does the variation differ in the different lakes? 



17. Are variations in one part of the body correlated with variations in 

 another part of the body? 



In many cases this can only be determined by converting the variations in 

 part into the terms of the variation of another part. The method for doing this 

 has been suggested by Galton, whose method is discussed at the end of this paper. 



18. What correlation is there in the variation of different species under the 

 same environment? 



As far as I am aware, no systematic studies of this description have been 

 made. With us this study resolves itself into the determination of whether the 

 fishes in Turkey Lake all differ from those in Tippecanoe along definite, deter- 

 mined ways, so that given the characters of a species for Turkey Lake the charac- 

 ters for the same species in Tippecanoe could be predicted. 



Similar but exotic instances are the absence of ventral fins in some of the 

 fishes inhabiting even widely separated mountain lakes, and the presence of en- 

 larged scales along the base of the anal in the Cyprinidfe inhabiting mountain 

 streams of India; or, to come nearer home, the peculiar color patterns of the 

 fishes in some regions of upper Georgia. 



