484 ~ BROOKLYN BOTANIC GARDEN MEMOIRS 
flowers and short spur branches were clustered at the extreme ends, 
giving a peculiar rosette-like appearance. The two types of fasciation 
were quite distinct on the plant, both as to general appearance and 
location. 
From the performance of these pedigreed cultures, it seems clear 
that the character of duplication and cohesion persists in successive 
generations of this variety of chicory to such an extent as to appear 
strongly heritable. It is not completely so, for a few normal single- 
stemmed plants do occur quite irregularly in various generations and 
lines of descent. 
The heredity of the character of duplication has also been tested by 
crossing plants of the 1915 crop showing typical fasciation with a 
plant of wild stock (plant A) which had a short, slender, main stem. 
No tendency to duplication has been seen in plants of wild stock which 
have been grown or in plants of various generations derived by crossing 
the wild plant A with plants of the cultivated variety known as Barbe 
de Capucin. This cross here in question involved, therefore, on one 
side parents with duplication, and on the other a plant of a stock 
free from duplication. : 
Thus far 81 plants of an F; generation have been grown; nineteen 
of these had the wild plant A as a seed parent. Of these 81 plants 
only three possessed the grooves which are seen in most typical cases 
of duplication of the main axis. In only one of these were the grooves 
pronounced (see no. 10); in the other two there were only slight indi- 
cations of grooves (see no. 11). In 78 plants there was not the slightest 
indication by grooves of any duplication. However, in tracing the 
phyllotaxy from base upward, irregularities were seen in 48 plants. 
Two leaves or branches were often opposite or the direction of the 
spiral would appear to shift from left to right or vice versa. In 30 
plants the spiral of the phyllotaxy proceeded very regularly from base 
to tip in a way that indicated a normal single stem-element (see no. 
12). Of the 19 plants having the wild plant for a seed parent, 7 were 
quite normal and in 12 there was a mixed or irregular phyllotaxy. 
Judged by performance in the F, generation, the character of 
duplication 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 regarding 
the sources, Causes, or nature of the stimulus operating in duplication 
nor any definite facts regarding the attending anatomical development. 
When this paper was presented it was suggested by Dr. Erwin F. Smith 
that possibly infection by some organism, bacterial or otherwise, was 
necessary to the development of duplication as here observed. If this 
