222 ANNUAL REPORT. OF THE Off. Doc. 



boiii^p: may varj some. In the state of nature, with few exceptions, 

 variations are comparatively sliglit, but in the state of domestica- 

 tion they occur more frequently and to a much greater extent. In 

 order to see striking illustrations of this, we have but to compare 

 various cultivated or domesticated Yorms with the wild forms, from 

 which they are known to have originated. In the improved breeds 

 man has introduced variation; man in his attempts to improve a 

 wild species for his use tries to induce variation. If he cannot se- 

 cure variation, the improvement must be very slight, so that varia- 

 tion is the thing that he tries to bring about first. 



After he secures variation, it is a comparatively easy matter to 

 direct that variation along the chosen or desired lines. The 

 variation in domesticated animals is greater than in wild species, be- 

 cause the domesticated animals are not of as pure a breed as are our 

 wild species and because the conditions under which they are main- 

 tained are not so uniform. The wild animals and plants are main- 

 tained under more uniform conditions than are our domesticated ani- 

 mals and plants. There is not only a greater mixture of blood in 

 the ancestry, but our domesticated animals are given a greater 

 variety of food. Breeders have learned that it is necessary to break 

 up the long line of uniform conditions if they would induce variation. 

 The history of the cultivated dahlia is an illustration of this. We now 

 have under cultivation very many beautiful forms, very many sizes, 

 colors and forms that have all come from one wild specie. This plant 

 was taken to France many years ago, from Mexico; an explorer in 

 Mexico found this plant and took it to France where it was cuiti- 

 vated for many years as a curiosity. They tried to improve it; they 

 subjected it to superior cultural conditions; gave it a better chance, 

 as we say. It grew a little larger, but the plant bore the same kind 

 of single flowers, not very beautiful, and they had about given up 

 securing an}' improvement when another traveler from Mexico took 

 anotlier variety of the same species to France. The botanists recog- 

 nized the two as belonging to the same species, but were different; 

 they were what we call local varieties. Then a florist took these two 

 varieties, bred them together, and thus in a little while he got 

 variation. He broke up that long line of ancestry and the 

 tendency to produce after its kind. It was not necessary that the 

 variation was in the right direction, but after a variation was oace 

 secured, then it was a comparatively easy matter to improve the 

 plant or its flowers, and that is just what the breeder of animals will 

 try to do. He Avill try to improve by securing variation, and by 

 breaking up long lines of ancestry. 



That is just what the Frenchman did — I didn't finish that story 

 about the English and French sheep. He tried to improve by cross- 



