74 BRACTS. 



The appendages of the Passijlora incarnata, Narcissus ia-^ 

 reta, and the several species of the Silene, are undoubtedly 

 modified petals, while many appendages found among the As- 

 clepiadese are as plainly modified Stamens. The term coro- 

 na is most commonly used by writers to designate every ap- 

 pendage which appears regularly around the centre of the 

 flower, whatever may be its origin. An appendage origina- 

 tino" from stamens is generally fleshy, and has bundles of ves- 

 sels corresponding to the number of stamens of which the 

 corona is composed. This fleshy part of the appendage has 

 received the name of orbicularis ; horn-like processes arising 

 from its summit are called cornua, the upper end of them is 

 the beak or rostrum ; and the back, if it is dilated and com- 

 pressed, is the ala or appendix ; horns proceeding from the 

 base of the orbiculus are called ligulcB ; the circular space in 

 the middle of the top of the orbiculus is called the scutum. 



The small appendage at the base of the petals of the Ra- 

 nunculus, Prof. Lindly thinks, is " a barren stamen united to 

 the base of the petal." 



The Spur, Calcar or nectarotJieca, is a hollow horn-like 

 appendage developed on the back and near the base of the 

 petal opening on the anterior face. Raspail considers this 

 appendage as later in its formation than the petal, and hence 

 concludes that it is rather an accidental organ, and that in 

 cases wherever it is not developed the petal is in its normal 

 condition, as sometimes happens in the Aquilegia. 



Most of the above forms were considered by the earlier 

 Botanists as nectaries, but with manifest impropriety, since 

 but few, if any, of them secrete honey. 



Bracts, 



85. There are often to be found organs situated between 

 the true leaves and the calyx, varying from them in outline, 

 color and size, which are called bracts. Many varieties of 

 bracts have been, till very recently, classed as varieties of the 

 calyx ; and some Botanists, even at the present day, adopt 

 this arrangement. The bract seems to occupy a space be- 

 tween the leaf and calyx, not only by collocation on the plant, 

 but in constitution and functions. They appear to perform 

 the same office in many cases as the calyx, and in others seem 

 not to differ in this respect from the true leaves. 



Their position and form, have given them various names, of 

 which the following are the most common. 



When they appear as simple scales on the peduncle, or at 



