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THE AMERICAN NATURALIST [Vol. XLV 



sive laciniation as the leaves approach the apex, com- 

 parable to the seasonal reduction of the blades in Acer 

 saccltariinihi var. Wieri, or of the various laciniate vari- 

 eties of Chelidonium ma jus referred to above. Also, 

 Professor Barr was able to gather seed. It should be 

 stated in this connection that while the seed of the 

 species, obtained from Albion, germinated readily and 

 produced typical Arctium seedlings, there appeared in 

 the seedpans devoted to the variety, seedlings having all 

 the characteristics of those of Lactuca Scariola integrata, 

 and these only. Seedlings of species and their varieties 

 are as a rule so much alike that the thought at once pre- 

 sented itself that some seed of the wild lettuce either had 

 become mixed with the seed of the variety or was con- 

 tained in the soil used for growing the seedlings. Were 

 either of these suppositions correct, it would seem 

 curious that the same thing had not occurred in the case 

 of the seed of the species. At least one of these possibili- 

 ties could have been eliminated had it been possible to sow 

 the seed in sterilized soil. As the rosettes grow older 

 there could be no doubt as to their really belonging to 

 Lactuca. While therefore these experiments yielded 

 negative results, it still is possible that their repetition, 

 with perhaps certain modifications, may result differ- 

 ently. Also an attempt should be made to obtain seed 

 from a different source, for it is very well possible that 

 while one lot of laciniate-leaved plants is fertile, another, 

 perhaps of distinct origin, is sterile. We find an analogy 

 in the case of Chelidonium ma jus laciuiatum quoted 

 above. 



Unfortunately but few herbarium specimens are avail- 

 able for comparison with the specimen of Darlington in 

 the Gray Herbarium. Through the courtesy of the 

 curators of the herbaria mentioned we learn that in the 

 herbarium of the Smithsonian Institution the variety is 

 represented by a single specimen "collected by Alfred 

 E. Rieksecker at Elyria, Lorain County, Ohio, August 1, 

 1894." It is added that it has very deeply laciniate 

 leaves and that the venation is very different from that 



