BIOGRAPHICAL SKETCH Ixv 
In consequence Professor Whitman’s work presents a great 
body of searchingly self-critical and reliable conclusions, and these 
conclusions unquestionably lead far into constructive evolution- 
ary theory. For his material he believed he had demonstrated 
beyond doubt the reality and regnancy of definitely directed 
variation, 1.e., of orthogenesis, as the method of evolution. He 
has accumulated and presented the most weighty evidences for 
continuity as against discontinuity in the phenomena of varia- 
tion, inheritance and evolution. He has thrown new light on the 
nature and meaning of ‘mutants;’ such ‘mutants’ at any 
rate as occur among pigeons. He accomplished in 1903, and con- 
tinuously since then, the remarkable result which in Mendelian 
terms may be spoken of as the control or determination of the 
dominance of sex and color.’ 
His work was most bountifully and beautifully illustrated, 
this feature having occupied many years of the undivided atten- 
tion of excellent artists. Even in the unfinished parts, however, 
the outlines of the work are so bold and its details of data are 
so clear as a result of the polishing process to which he, who 
was the very spirit of clarity and accuracy, subjected them, that 
time and care will enable others to arrange most of the results 
in a form that will still carry conviction to the reader. 
Whitman’s conception of Orthogenesis, and his attitude toward 
the mutation theory is stated in the following paragraph: 
‘‘ Among the rival theories of natural selection two are especially 
noteworthy. One of these is now generally known as ortho- 
genesis. Theodore Eimer was one of the early champions of 
this theory, basing his arguments primarily upon his researches 
on the variation of the wall-lizard (1874-81). Eimer boldly 
announced his later works on ‘The Origin of Species’ (1888), 
and the ‘Orthogenesis of the Butterflies’ (1897), as furnishing 
complete proof of definitely directed variation, as the result of the 
inheritance of acquired characters, and as showing the utter ‘impo- 
tence of natural selection.’ Eimer’s intemperate ferocity toward 
the views of Darwin and Weismann, coupled with an almost 
7 Unpublished data. 
