i893. NOTES AND COMMENTS. 167 



More Notes ox Seedlings. 



The January Bulletin of the Torrey Botanical Club opens with 

 some "Studies upon Akenes and Seedlings of Plants of the Order 

 Compositse," by W. W. Rowlee, illustrated by five plates. The 

 account, which occupies 17 pages, is much less comprehensive than 

 that given in Lubbock's recent work (vol. ii., pp. 98-161), and 

 the general obser\ations are of less value, being based on fewer 

 experiments. Thus the cotyledons, we are told, vary in shape from 

 spathulate to orbicular, but Lubbock gives several instances of linear 

 cotyledons, — -Bidens Inoiiilis, species of Ui'sinia, and Coreopsis gigantea ; 

 the American author describes one species of Coreopsis (C. discoidea), 

 which, however, like another species (C laciniata) included by Lubbock, 

 has broader cotyledons. Nor is any mention made of the interesting 

 polymorphy of achenes, which obtains in the Old World genus 

 CaleuduJa. Mr, Rowlee's studies form, however, a valuable addition 

 to our knowledge, as the greater number of his species are not 

 included in the larger work, and the genera are in many cases 

 unrepresented. ?^Ioreover, figures are given of every species 

 described, both of the fruit and seedling, and often two or more 

 stages of the latter. 



The cotyledons of the Ox-eye Daisy are oblong, like those of the 

 Corn Marigold and another species of Chrysanthemum (C. carinatum) 

 figured by Lubbock, but Rowlee makes the two following leaves 

 spathulate and entire, thus differing widely from their deeply-toothed 

 character in the other two species. The seedling of the Yarrow 

 corresponds with the description in the English work, except that there 

 is no mention of any hairiness on the first leaves ; it would be in- 

 teresting to know whether they are glabrous in the New World, or the 

 hairs have been merely overlooked. One Artemisia is described, viz., 

 Wormwood (^. Absinthium), and its seedlings, we are told, may be 

 distinguished from those of the Yarrow by the oblong shape and 

 entire margin of the second and third leaves after the cotyledons. 

 Comparison with the larger treatise shows that this is not a generic 

 distinction, for there we find that in A . annua the corresponding leaves 

 are three-toothed as in the Yarrow though in another species (A. 

 Mutellina) entire. 



The Helianthus {H. divaricatus) mentioned bears a general 

 resemblance to //. cucumerifolius, included by Lubbock, the cotyledons 

 being ovate and obovate respectively, while in each case the first 

 internode and following leaves are somewhat densely hairy. 



In speaking of the embryo, cotyledons and hypocotyl are in- 

 variably distinguished, the latter term including everything below the 

 cotyledons, and consequently the radicle. This seems a pity ; the 

 radicle is an organ so well marked, not only from a morphological, 

 but also from physiological and anatomical points of view, that it 

 is a pity to ignore or slight its presence in the earliest stages. 



Some remarks are also made on the germination of the seeds. 



