XLYI. ROSACE.E 277 



OEnER XLVI. ROSACEiE. Gen. PL i. 600. 



Herbs, slirubs or treefe, 1. stipulate; alternate, rarely opposite, bimple or com- 

 pound. Fl. as a rule regular and bisexual : calyx gamobepalous, free or adnata 

 to ovary, lobes 5, imbricate in bud. Disk annular or lining the calyx-tube ; 

 petals 5, perigynous, rarely wanting, often orbicular and concave, deciduous, 

 claws short or none, imbricate, rarely contorted in bud. Stamens as a rule 

 numerous, inserted with the petals or on the disk, incurved in bud. Carpels 

 usually distinct, one or more, often adnate to calyx-tube, styles free or connate, 

 ovules in each carpel 1 or 2, rarely more. Fruit often fleshy. Albumen none or 

 scanty, cotyledons plano-convex, cellb filled with oil, radicle short. 



Apart from medullary rays, parenchyma does not form an important part in the 

 wood of Eosacese. Ohryhobalanecc {Parinai ium, Para^temon) are exceptional, they have 

 narrow tangential bands of parenchyma m the wood. In this respect, as well as in the 

 more or less zygomorphic fl, this tribe approaches Le<juminoi>m, Wood fibres in 

 JRosffCPce as a rule have not bordered pits. As far as known, the %\ood of the climbing 

 species has a normal structure. 



A. Eipe carpels not enclosed within the calyx-tnbe. 



(See KeiUla and Sjnrcea cr/«fsve;?s.) 



I. Leaves simple, quite entire. Carpel one. Fl. usually zygomorphic (tribe 

 Chr(jsobaIa7ie(^). 

 Calyx-tube elongate, stamens 6-30, usually 



unilateral 1. Pabinarium. 



Calyx-tube short, stamens 2 .... Pahastemon (p. 278). 



IT. Leaves simple, serrate. Carpel 1, rarely 2. 

 Calyx 5-lobed, petals large. 



Style terminah stone hard, bony . . .2. Prunus. 



Style basal, endocarp coriaceous . . .3. Prinscpia. 

 Calyx 5-10-toothed, petals minute or 0. 



Carpels 1 or 2, stone hard, bony . . , Madden i a (p. 281). 



Carpels 1, endocarp coriaceous . . . .4. PygtEum. 



III. Leaves simple or compound. Calyx without bracts. 



Carpels 1-8, ovules 2 or more, fr. dry. 

 Seeds linear, testa membranous, albumen or 



scanty 5. Spir.-ea. 



Seeds globose, testa crustaceous, albumen 



copious Neillia (p. 288). 



Carpels oo , ovules 2, fr. usually fleshy . . 6, Ritbus. 



IV. Leaves usually compound, calyx bracteolate, fr. dry Potentilla (p. 287), 



B, Bipe carpels enclosed within the calyx-tube. 



I. Carpels co free, when ripe enclosed in the fleshy 



calyx-tube 7. Rosa. 



II. Carpels connate, forming a 1-5-celled ovary, more or less adnate to calyx- 

 tube, which in fruit is fleshy, enclosing them. 

 Ovary 5-celledj 3 or more ovules in each cell. 



3 ovules in each cell 8 Docynia. 



Many ovules in each cell .... 

 Ovary 2-5-celled, 2 ovules in each cell. 

 Ovary 5-celled, fl. panicled 

 Ovary 2-5-celled, fl. corymbose or fascicled. 



Pr. 2-5-celled 



Drupe with 5 dehiscent stones 

 Ovary 2-3-celled, endocarp thin. 

 Testa coriaceous or membranous . 

 Testa thick, reticulately lacunose 

 Ovary 2-5-celied, drupe with 1-5 bony stones 

 Leaves cut, toothed or serrate 

 Leaves quite entire .... 

 Leaves imparipinnate .... 



9. Cydonia. 



10. Eriobotrya. 



11. Pyrus. 



12. SrRAKV.¥.SIA. 



13. Photinia. 



14. pourthijca. 

 (pyrenes). 



15. CRATiEC^US. 



16. COTONEASTER. 

 OSTEOMELES (p. 295.) 



