84 



PRINCIPLES OF PLANT-TERATOLOGY. 



bud has (congenitally) occurred. It is thus seen that 

 dichotomy is not at all uncommon in Dicotyledons : 

 as an abnormal phenomenon, it is true ; but we have 



b 



Fig. 23. — Lonicera Periclymenum. a. Leaf beginning to fork • bud 

 still undivided, b. Leaf and bud both dichotomized, c. Diagram 

 of leaf and axillary bud, each of which has just dichotomized. 

 (After Celakovsky.) 



yet to learn what is the essential distinction between 

 the normal and the abnormal. In Monocotyledons it 

 was seen in an orchid of trigeneric hybrid origin 



Fig. 24. — Ruscus aculeatus. a. Cladode showing equal dichotomy. 

 b. The same showing unequal dichotomy. (After Celakovsky.) 



(Brasso-Gattlaelia x Fowleri) in which the pseudo-bulb 

 forked into two ; the cladodes of the butcher's broom 

 {Ruscus aculeatus) quite frequently exhibit it (fig. 24). 



