1895.] Antidromy in Plants. 975 
of every species into a right-handed and a left-handed caste ; 
and even when sunlight interferes, we often get help from 
js A 
Fig. 4.—Richardia africana Kunth. 
branches in the shade. Examples of it abound in all the more 
important orders of plants, and there seems to be no exception, 
though in opposite-leaved forms the evidence from phyllotaxy 
is not easily available. I have found no case of heterodromy as 
between the true foliage leaves of an individual plant; and the 
only case in which I have failed to observe antidromy between 
different plants is the Canna, which is mostly propagated by 
bulbs. (Doubtless there are specimens with a right-handed 
twist of the young leaves, though I have failed to find any.) 
In a bed of Lily of the Valley, half of the specimens have the 
inner leaf diverging 120° to the right, and the rest have simi- 
lar divergency to the left. (Fig. 5.) In this, as in other 
Liliaceze, the anthotaxy 
will be found to vary in 
harmony with the phyl- 
lotaxy. 
Doubtless the anti- 
dromic phyllotaxy causes 
a corresponding anti- 
dromy of the leaf-traces, 
and of structure of the 
stem. This has escaped 
anatomists who expected 
symmetry; but some of 
the figures in the books 
show a trending of leaf- 
