66 



has the same percentage of purple florets as the wild one, al- 

 though they have rarely seen more than one purple floret to 

 the umbel. L. H. Bailey writes that in a good number of speci- 

 mens of the cultivated carrot, there is no trace of a purple 

 flower. This, however, pro^•es nothing, for as we have seen 

 many of the umbels of the wild carrot do not show it. Direct 

 observation has been difficult, as most farmers do not grow 

 their own seed. 



Certain marked differences between the wild and cultivated 

 strains, presumably genetic, stand forth. Such concern the 

 characters of edibilits", texture of the root, color, etc. It is 

 interesting at this point to recall the experiments of Vilmorin, 

 (Le Bon Jardinier, 1838, p. 16; 1840, p. 195), by which he showed 

 that 3 or 4 generations of cultivation of the wild strain caused 

 it to assume the characters of the cultivated form, especially 

 the ones cited. He obsers'ed a gradual transition between the 

 wild and cultivated forms. Mlmorin's experiments were 

 vigorously attacked at the time, other botanists claiming that 

 the results were due to accidental hybridization with the culti- 

 vated form, and that the characters of the wild strain were 

 immutable ones. The burden of evidence since accumulated 

 has been in favor of \'ilmorin, if only on account of the method 

 of origin of the cultivated carrot. While genetic studies on the 

 wild carrot have been contemplated by some, they have not 

 been made, and until such a time, it is not very profitable to 

 speculate upon the causes of these obser\-ed differences. How- 

 ever in the light of our knowledge concerning other plants, one 

 may well understand how differences in genetic strains may 

 account for the qualitative and quantitative differences observed, 

 provided the divergent variation, as manifested even in the 

 small amount of material studied, be taken into consideration. 

 Environment looms up as an important factor when the origin 

 of the wild carrot is taken into consideration Knuth (Bliiten- 

 biologie III), indicates species of aphids and wasps as the source 

 of pollination while I have also obser\ed a protectively colored 

 spider and certain beetles in association. An additional clue 

 possibly of aid in pursuing such a study would seem to lie in 

 the fact that if one plant has an umbel with a dark central 

 flower, nearly all the umbels on the same plant ha\'e it. 

 Washington and Jefferson College 



Washington, Pennsylvania 



