ROSACEAE 571 



petals, or oo or i 4. Ovules anatr., usu. 2 in each cpl. Style often 

 lat. or basal. Fr. various, dry or fleshy; often an aggregate of 

 achenes (Potentilla) or drupes (Rubus), or a single drupe (Prunus), 

 or pome (Pyrus), and so on (cf. genera, esp. those mentioned, and 

 Fragaria, Geum, Rosa, Poterium). Seed usu. exalbum. 



Fls. in general of simple type, with slightly concealed honey and 

 oo sta., usu. protandrous. Poterium sp. are anemoph. 



Few are of economic value (see Pyrus, Rubus, Fragaria, Prunus), 

 but many are favourites as garden plants and shrubs. 



Classification and chief genera (after Focke). Closely related to 

 Saxifragaceae, some genera being almost arbitrarily placed in one 

 or the other; also nearly allied to Calycanthaceae, Combretaceae, 

 Myrtaceae (floral diagram of M. practically the same as that of II), 

 Thymelaeaceae, and Leguminosae (through VI). 



I. SPIRAEOIDEAE (cpls. 121, usu. 52, whorled, neither 

 on special carpophore nor sunk in recept., with 2 or more 

 ovules in each; fr. usu. dehisc. ; sta. on broad base, tapering 

 upwards ; stipules often absent) : 



1. Spiraeeae (follicle, seeds not winged): Spiraea. 



2. Quillajeae (follicle, seeds winged) : Quillaja. 



3. Holodisceae (achene) : Holodiscus (only genus). 



II. POMOIDEAE (cpls. 5 2, united to inner wall of recept., 

 usually syncarpous; axis fleshy in fruit, stipules) : 

 Pomarieae: Pyrus. 



III. ROSOIDEAE (cpls. oo or rarely i on carpophore, sometimes 



enclosed in axis in fr. ; fr. i -seeded indeh.) : 



1. Kerrieae (slips, distinct; axis not forming part of fr. ; sta. 



tapering upwards from broad base; cpls. few, whorled; 

 sta. oo ) : Rhodotypos, Kerria. 



2. Potentilleae (as 5, but cpls. usu. oo, in a head, or rarely few 



and then sta. also few) : 



2 a. Rubinae (drupes, no epicalyx) : Rubus. 

 2 b. Potentillinae (achenes; seed pend. ; usu. epicalyx): 



Fragaria, Potentilla. 

 2 c. Dryadinae (as b, but seed erect): Geum, Dryas. 



3. Cercocarpeae (stipules slightly developed; torus tubular; 



cpl. r; achene): Adenostoma, Purshia. 



4. Ulmarieae (torus flat or nearly so; sta. with narrow base) : 



Ulmaria. 



5. Sangtiisorbeae (torus cup-like enclosing cpls., hardening in 



fr. ; cpls. 2 or more): Alchemilla, Agrimonia, Poterium. 



6. Roseae (torus cup-like or tubular, enclosing oo cpls., and 



fleshy in fr.) : Rosa. 



IV. NEURADQIDEAE (cpls. (510) united to torus, which is 



dry in fr. ; herbs). 



Neuradeae: Neurada. 



V. PRUNOIDEAE (cpl. i, rarely 25, free of torus; drupe; 

 trees with simple 1.; style almost term.; ovules pend.; fls.reg.). 



Pruneae: Nuttallia, Prunus. 



VI. CHR YSOBALANOIDEAE (as V, but style basal and ovules 

 erect) : 



