. Dedication papers : scientific papers presented at the dedication of the laboratory building and plant houses, April 19-21, 1917. ld appear to shift from left to right or vice versa. In 30plants the spiral of the phyllotaxy proceeded very regularly from baseto tip in a way that indicated a normal single stem-element (see ). Of the 19 plants having the wild plant for a seed parent, 7 werequite normal and in 12 there was a mixed or irregular phyllotaxy. Judged by performance in the Fi generation, the character ofduplication is only incompletely and partially dominant. An inter-mediate typ
. Dedication papers : scientific papers presented at the dedication of the laboratory building and plant houses, April 19-21, 1917. ld appear to shift from left to right or vice versa. In 30plants the spiral of the phyllotaxy proceeded very regularly from baseto tip in a way that indicated a normal single stem-element (see ). Of the 19 plants having the wild plant for a seed parent, 7 werequite normal and in 12 there was a mixed or irregular phyllotaxy. Judged by performance in the Fi generation, the character ofduplication is only incompletely and partially dominant. An inter-mediate type is frequent in which the only suggestion of a duplex con-dition of the main axis is seen in an irregular phyllotaxy. I cannot at the present time contribute any information regardingthe sources, causes, or nature of the stimulus operating in duplicationnor any definite facts regarding the attending anatomical this paper was presented it was suggested by Dr. Erwin F. Smiththat possibly infection by some organism, bacterial or otherwise, wasnecessary to the development of duplication as here observed. If this. STOUT: DUPLICATION AND COHESION 485 should be the case it is evident that while the susceptibility is verydecidedly limited to the variety it can be transmitted directly orindirectly though incompletely to large numbers of the offspring of ahybrid generation. Summary An unusual type of fasciation occurs in the variety of chicory knownas red-leaved Treviso. It consists of a very decided duplication inthe main axis of the stem, giving two stem-elements with, however, adecided cohesion of the two. In this variety of chicory there are alsovarious irregularities in the development of cotyledons and degrees of fusion between the two cotyledons are in evidence; insome seedlings only one cotyledon is present. Occasionally no plu-mule develops. The character of duplication and cohesion of the main axis isstrongly but not completely heritable. There is
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectplants, bookyear1918
