NOTE 
A NOTE ON AN ABNORMALITY IN THE STEM OF HELIANTHUS 
ANNUUS. — The stem of the Sunflower has been the subject of such frequent detailed 
examination that it is surprising that so few cases of abnormal structure have been 
recorded. This is also the case with many other plants which have been selected 
as types for laboratory work. In the course of such treatment large quantities of 
material are cut up and examined, with the result that every opportunity is provided 
for gaining a knowledge of the range of variety of structure. The uniformity of the 
results of such examinations serves only to emphasize the remarkable constancy with 
which the typical structure is maintained. 
The particular variation in structure met with in this instance was found in 
a short length of stem taken from a young plant of Helianthus annuus. 
Unfortunately only a small portion of the material showing the abnormality was 
found, and it did not include a node. However, there were sufficient differences in 
structure between the two ends of the specimen to suggest a possible explanation of 
the mode of origin of the peculiarities about to be described. 
[Annals of Botany, Vol. XXX. No. CXIX. July, 1916.] 
