76 ARRANGEMENT OF FLORAL LEAV^ES 



(fig. 213). In the Orchids the stamens and style combine to 

 form a central column. 



Disk. — Frequently the receptacle of a flower has upon it 

 certain subsidiary outgrowths, which collectively form the disk. 

 The disk may take the form of a whorl of two or more little 

 swellings {e.g. Geranium, Chickweed) or scales ; or it rnay be 

 in the form of a single horse-shoe-like or ring-like outgrowth at 

 the base of the style or stamens (e.g. Daisy-family), or may be a 

 lining to the concave receptacle (e.g. Rose). Very frequently 

 the disk secretes honey : in which case it is a nectary or a 

 collection of nectaries. 



