S« LUTHER fiURBANK 



It has alreacijr been ttid that the apfMaranee of 

 a fra^ant calla conttitutai such a chan^cf . But of 

 oourte the anomalies that are tisiially luted as 

 mutations are often of an even rooTB notioetbk 

 character. A classical iUustimlion wet fhrcn by 

 DarwiB hkiaelf in the eeae of the Aneon ram. 

 which WMs bom with \efi% only half the normal 

 len^h. and from the pn»Kri nhieh was 



developed a short«>l«gfed race ot taiecp. 



I^it the word mutation had not eome into 

 vogue in Darwin's time, and the idea of evolution 

 through such marked departures f mm the normal 

 was 8ul>ordinated in Darwin's interpretation of 

 the origin of tpecies. or at lea«t in that nf his 

 iiimiediate followers, to the idea of advnmv^ 

 through the preservation of sliglit variation v 



So when, just at the close ot the ninettdith 

 centur>% Professor Hugo de Vries came fo? 

 with his "mutation theory," it had all the foiv ^ ^^m 

 a new doctrine, and was even thought by some 

 enthusiasts — though not by its originator — to be 

 in conflict with the chief Danvinian doctrines. 



The observations that led Professor de Vries 

 to the development of this theory were made on a 

 familiar American plant that had found its way 

 to £urope and was growing in profusion by the 

 roadside near Amsterdam. The plant is known 

 as the evening primrose. 



