241 



mental purposes, at the propagating house of the New York Bo- 

 tanical Garden, in August, 1907. Young plants appeared upon 

 old and apparently dead leaves, which were attached to the plant 

 and were at first thought to be seedlings that had penetrated the 

 leaf-tissue in their growth. Sections showed that this was not 

 the case, but that the young plant grew from the cells of the old 

 tissue, which had remained in an embryonic condition. No for- 

 mation of callus was observed. Regeneration occurred with equal 

 facility from blade or petiole of the leaf or from the flower-stalk. 

 The first leaves of the young plant bear no tentacles, but later 

 leaves are exactly like those of the parent plant. The roots 

 appear after the stem has attained some size and are at first di- 

 ageotropic but later bend toward the substratum. 



Droscra is not mentioned in recent literature upon regenera- 

 tion, but Spencer, in his "Principles of Biology," 1867, referred 

 to the subject as a matter of common knowledge. Naudin re- 

 corded the appearance of a bud upon the upper surface of the leaf 

 of D. inter )ncdia in Ann. Sci. Nat. II. 14: 14. pi. i. Jig. 6. 

 1840. Planchon gave his observations upon certain "monstrous 

 flowers" of D. intermedia in Ann. Sci. Nat. III. 9: 86. pi. j & 

 6. 1853. His observations were verified by various later writers. 

 The most extended study of regeneration in D. rotundifolia was 

 made by Nitschke, professor at Westphalia, whose investigations 

 were printed in the Bot. Zeit. 8: 237, 239, 245. i860. He 

 studied plants in the bogs and observed that the age of a plant 

 could be determined by the successive rings of young plants 

 about it. 



Photographs of regenerating plants and of sections showing the 

 relation of the regenerating tissue to the parent plant were shown, 

 also specimens in alcohol, demonstrating the origin of young 

 plants from petiole and blade of leaf and from the flower stalk. 



Norman Taylor: Notes on Tinnboa {Welwitschia). 



After a short account of the history and synonymy of Twnboa 

 Bainesii ( Welwitschia mirabilis), a general description of the mature 

 plant was given. Attention was called to the peculiar characters 

 of Tiunboa, which is exogenous in the two cotyledons and the 

 2-4-merous perianth, endogenous in the parallel-veined leaves 



