124 XXIV. EOSACEAE. [Frunus. 



Oedbe XXIV.— R0SA,CEAE. 

 Calyx of 5, 4^ or rarely 3 sepals, imbricate or valvate in sestivation, united 

 at the base, inferior or superior. Petals as many as the sepals, rarely 0, free, 

 inserted on the calyx, imbricate in sestivation. Stamens oo or rarely few, in- 

 serted with the petals. Carpels ] or more, connate, or adnate to the calyx-tube ; 

 styles free or connate ; stigma simple, rarely plumose or winged ; ovules 

 anatropous ; embryo straight. Endosperm or rarely scanty. Fruit various, 

 of 1 or many drupes, achenes, or follicles, rarely a pome, berry, or capsule. 

 Radicle short, straight. Cotyledons plano-convex. Herbs, shrubs, or trees, the 

 stems often armed with prickles or thorns. Flowers hermaphrodite or uni- 

 sexual. 



A large order, containing about 1,250 species, arranged under 80 genera, distributed through 

 nearly every country in the world, from Lapland to Macquarie Island. Most of the New Zealand 

 species are endemic. 



* Bipe carpels not enclosed within the calyx-tube. 

 Tribe I. PEUNBAB. 



* Peunus. Stem woody. Calyx deciduous. Fruit a drupe. 



II. EUBBAE. — Calyx persistent, ebraoteolate. 



1. EuBus. Stems prickly. Bruit of many small drupes on a dry receptacle. 



III. POTENTILLEAE.— Calyx persistent, braoteolate. Carpels 1-ovuled. 



2. Gbum. Leaves pinnate. Scape 1- or many-flowered. Styles hooked. 



* Fkagabia. Leaves 3-foliolate. Receptacle pulpy, bearing achenes on its surface. 



3. POTENTILLA. Leaves pinnate or digitate. Achenes on a dry receptacle. 



** Bipe carpels enclosed in the calyx-tube. 



IV. POTEEIEAB. — Carpels 1-3 ; ovule 1. Achenes enclosed in the dry calyx-tube, which 



is constricted at the mouth. Petals 0. 



* Alchemilla. Calyx 4-5-lobed. Stamens 1-4. 



* PoTEBiDM. Calyx-lobes 4, petaloid. Blowers capitate. 



4. AOAENA. Pruiting-calyx usually armed with barbed spines. Stamens few. Stigmas 



plumose. 



V. EOSEAB. — Carpels many, included in the globose receptacular cavity ; ovule 1. 

 Stipules adherent with the petiole. 



* EoSA. Shrubs with unequally pinnate leaves and prickly stems. 



VI. POMEAE.— Carpels 1-5; ovules 2 in each carpel. Bruit a pome or drupe, inferior. 

 Stipules free. 



* Ceataegus. Usually thorny shrubs or trees. Bruit resembling a drape, inferior, 



with 1-5 bony stones or nuts. 



* PRUNUS, Linn. 

 Calyx deciduous, 5-lobed, imbricate. Petals 5, perigynous. Stamens 15-20 

 free. Carpel 1 ; ovules 2, pendulous. Fruit an indehiscent fleshy drupe with a 

 smooth or rugose bony nut. Seed pendulous. Endosperm or scanty. Shrubs or 

 trees, with alternate leaves, and usually with edible fruit. 



Blowers on slender peduncles. Endocarp smooth . . . . . . . . * P. cerasus. 



Blowers sessile. Endocarp rugose . . . . . . . . . . . . * P. Persica. 



* P. cerasus, L., Sjy. PL 474. An erect shrub, 6ft.-9ft. high or more. Leaves 



alternate, erect, with two glands on the short petiole, obovate-oblong, acuminate, 



doubly crenate, serrate. Flowers on short peduncles, solitary or in few-flowered 



umbels. Calyx-tube not constricted. Drupe small, rounded, not glaucous. 



NOETH and SOUTH Islands: increasing by suckers, and sometimes forming small groves. 

 Small cheiry. Sept. Europe, &o. 



