94 A TEXTBOOK OF GENERAL BOTANY 
are frequently covered with oummy or resinous substances ney 
afford excellent protection to the bud. 
The bracts which cover some types of unopened flowers are 
also modified leaves which have a protective function. 
In this category we may also include the reduced leaves of 
parasitic and saprophytic plants. Such plants do not produce 
chlorophyll, and have only small reduced leaves whose only 
function would seem to be that of protecting the buds. 
