THE ANGIOSPKRMAE : LEAVES 



1045 



myrmecophily, etc., and examples of these will be dealt with in X'olunie 1\'. 

 They are perhaps commoner among floral leaves than among foliage leaves, 

 and m the flower they are often used as nectar containers. The " spurs " 

 and " honey sacs " of many flowers belong to this category, and also the 

 floral pouches of Cypripedium and Calceolaria. 



5. Buds on Leaves. — These are exceptional occurrences and almost always 

 associated with vegetative propagation. The buds are rarely of the bulbil 

 type and mostly take the form of small leafy rosettes, which are usually 

 detachable. We may classify them into two biological categories : — 



Accessory buds, which are formed on the normally growing leaf blade or 

 the petiole, either on the ventral surface, as in Cardamine prafensis, Tellinia, 

 Drosera, Lycopersicum or Nymphaea zanzibarensis (Fig. 1041 ), or on the margins 

 as in Bryop/ivlliiin temiifoliutn. 



«(-. 



\ 



Fig. 1040. — Bergenia cordifdha. 

 An ascidial leaf. 



Fig. 1 04 1. — Svmpluua ziinzibaremis. Old leaf showing 

 the de\ elopnient of accessory buds at the base of the 

 lamina. 



Reparative buds, which develop after separation or injury of the leaf, 



be 



as in Begonia, Ficus elastica and Bryophyllum calycinum. They 

 described' further in Volume IV, under the heading of Vegetative Pro 



wu 



pagation. 



