270 



lu order to estimate the effect of deviations of one organ upon the rest of the body, 

 it is necessary to measure the average character of the rest of the body in indi- 

 viduals with vai-ving magnitude of the given oigan." 



Conclusions reached by an application of these principles to a study of the 

 shore crab gave as a result that — a. There is a period of growth during which 

 the frecjuency of deviations increases, h. That in one case the preliminary in- 

 crease is followed by a decrease in the frequency of given magnitude, in the other 

 case it was not. c. Assuming a particular law of growth the observations show 

 a selective destruction in the one case and not in the other. 



8. What is the relation of the annual fluctuation (mutation) in variation to 

 the annual fluctuation in the different elements of the environments? 



!>. What is the difference in the variation of the youngest brood early in the 

 season and late in the season, and what is the difference in the variation in suc- 

 ceeding years of the same brood? Is this difTerence, if any exists, due to modi- 

 fications with age or to selective destruction, /. e., has a larger percentage of 

 individuals with one characteristic been eliminated than of individuals, with 

 this characteristic slightly different? In what part of the curve of variation 

 have the greatest changes been produced ? 



10. If certain individuals with definite characters seem to survive, can it 

 be determined in what way this variation brings about the survival? 



11. At what age or stage of growth are variations greatest? 



12. Can variations arising with age be referred to habits or environment? 

 lo. What is the relation of sports or saltatory variations to the continuous 



"variation numerically? 



By saltatory variations are meant all those variations not connected with the 

 iuean by intermediate steps. 



14. Are saltatory characters always bilateral? If not, to what degree are 

 they bilateral? 



The fact that a saltatory variation is confined to one side or is found on both 

 sides, may enable us to determine whether the deviation began in the germ before 

 the appearance of bilaterality or is of later origin. 



15. In how far is the repetition of a character due to the repetition of the 

 environment as shown in the correlation of annual fluctuations in environment 

 with annual variations? See under 8. 



Whitman Biological Lectures, 181)4, p. 4: ''An epidemic of metaphysical 

 physics seems to be in progress— a sort of neo-epir/eiie.-iis. In i)lace of the ris 

 essendalvf of the old epigenesis. the new epigenesis sets uj) as its letich the m 

 impres.-ia. The new god is preferred because it works from the outside instead of 



