Rosaceae 



57 



disturbances of this arrangement by abortion occur. 

 Stamens with short filaments and clavate anthers with 

 peltate prolongation of connective. Carpels free with 

 1-2 almost orthotropous ovules with two integuments. 

 Fruit a caryopsis. Endosperm scant)-. 



*Platanus. 



Fam. 4. Rosaceae. Herbs, shrubs or trees. 

 Leaves spiral. Stipules sometimes adnate to petiole, 

 rarely absent. Flozvers cyclic, usually heterochlamy- 

 deous, actinomorphic, rarely zygomorphic. Flower-axis 

 flat, dish- or cup-shaped : sometimes convex in the 

 middle. Sepals^ petals and staj?iens on the edge of the 

 axis, perigynous or epigynous. Petals often orbicular 

 and concave. Stamens mostly 2-4 times as many as 

 sepals, or 00 , rarely 1-5, bent inwards in bud. Cajpels 

 as many as sepals or 2-3 times as many or 00 , rarely 

 1-4, free or united with the inner wall of the flower-axis, 

 i-locular with usually two anatropous ovules. Styles 

 apical or on ventral side of carpels. Fruit follicular or 

 indehiscent, or drupaceous or a false fruit by union of 

 carpels with flower-axis. Endosperm scanty or absent. 

 Cotyledo7is mostly fleshy, plano-convex. 



Subfamily ^Spiraeoideae. Filaments narrowed up- 

 wards from broad base. Carpels 12-1 whorled, rarely 

 sunk into flower-axis or on gynophore. Ovules 00 -2. 

 Fruit usually of follicles. 



* Tribe Spiraeeae, Shrubs rarely herbs. Seeds not 



winged. 



*Spiraeat. 



t The plants often known in Britain as S. Ulmaria and S. 

 Filipendula belong more properly to the genus Ulmaria, subfamily 

 Rosoideae, tribe Ulmarieae. 



