344 Bulletin 278. 



on a heavy soil. Therefore, in describing varieties it is important to 

 know which characters are comparatively stable and which variable, 

 in order that more prominence may be given to the stable characters. 

 Definitions of the eight horticultural types, which have been taken as 

 standards, may be found elsewhere in this bulletin. (Pp. 227-229.) 



After a careful study of the peony bloom, the following characters 

 have been selected as suitable for use in the descriptions : 



Differentiation. — When the guards or primary petals are longer, 

 larger, and quite distinct from the petaloids which result from doubling, 

 we say the flower is "differentiated." If it is difficult to determine 

 where the petaloids stop and the guards begin, we say the bloom is 

 "not differentiated." 



Staminodes are those petaloids which have resulted from the trans- 

 formation of stamens. They are usually much smaller and narrower 

 on the outside, and gradually widen and enlarge inwardly. They may 

 be uniform or decidedly irregular, erect or reflexed. 



Carpelodes are those petaloids in the center of the bloom which have 

 resulted from the transformation of carpels. They may usually be 

 recognized by being much larger and more showy, but fewer in number 

 than the staminodes. 



Petaloids. — This is simply a general term combining both staminodes 

 and carpelodes. 



Secondary Staminodes and Carpelodes. — It often happens that the 

 peony in doubling will produce a sort of two-storied flower. We find 

 within the carpelodes another set of secondary stamens or staminodes, 

 and within these again secondary carpels or carpelodes. In a few cases 

 we find the peony doubling with apparently no system, where all these 

 different parts are jumbled up together; but such cases are rare, and 

 usually little difficulty will be found in recognizing the primary and 

 secondary parts. 



Carpels. — In simple, single flowers the carpels are the divisions of the 

 ovary which bear the seed. When ripe they may be called follicles. 

 In some species they are strongly apprest, in others curved back and 

 away from each other. This is hardly a varietal characteristic, and is 

 not considered of value in separating varieties of P. albiflora. 



In the descriptions made in Bulletin 259, considerable importance 

 was attached to the color of the carpels. Studies the past year indicate 

 that little or no reliance can be put on this characteristic, especially 

 if the carpel has been exposed to the sunlight. It was noted that 

 carpels which were a pinkish green when the bloom first opened, turned 



