ROSE FAMILY 139 



horny or stony carpels are imbedded in a fleshy adherent calyx- 

 tube, comprising the Apple, Pear, Quince, Medlar, Rowan, and 

 Hawthorn. All the cultivated varieties of Ap'Jile are derived from 

 the wild Crab, Pirns Mains, and the Pears from a thorny tree, 

 with a hard astringent fruit, Pirus communis.^ The wood of the 

 Pear is very close-grained and is used in making T-squares. 

 The fruit of the Rowan, and some other s.pecies, yields malic 

 acid, and the leaves as much prussic acid as those of the Cherry- 

 Laurel. 



Tribe 1. P>-uuuc. — Leaves simple: calyx deciduous: fruit a 

 drupe. 



1. Prunus. — Stone smooth. 



Tribe 2. Spirece. — Calyx persistent : carpels -, or more : fruit an 

 etcgrio of follicles. 



2. SpiR-€A. — Sepals .\ — 5; carpels -^ — 12. 



Tribe 3. Ri'ibeJe. — Calyx persistent : carpels many : fruit an etano 

 of drupels. 



3. RuBUS. — Receptacle convex, spongy; ovules 2 in each 

 carpel. 



Tribe 4. Poientillece. — Calyx persistent, ivitli an epicalyx : carpels 

 4 or mo?-e : ovules i in each ca7pel : fruit an etisrio of aclienes. 



3. Drvas. — Leaves simple; scape i -flowered ; stjles becoming 

 feathery. 



5. Gfu.M. — Leaves pinnate ; scape several-ffowered ; styles be- 

 coming hooked awns. 



6. Fragaria. — Leaves ternate ; aclienes oh fleshy receptacle; 

 style not elongating. 



7. PoTENTlLLA. — Leaflets 3, 5, or many, palmate or pinnate ; 

 stamens many ; aclienes many, on dry flat receptacle ; style not 

 elongating. 



8. SiBBALDlA. — Leaves ternate; stajnens 5"; aclienes 5 — 10, on 

 dry concave receptacle. 



9. CoirARUM. — Leaves pinnate ; stamens many ; receptacle coni- 

 cal, becoming large and spongy, persistent. 



Tribe 5. Pota-iccE. — Petals 5 or absent : carpels r- 5 -.fruit r — 5 

 achenes {i-seeded) enclosed in small dry calyx-tube. 



10. Alchemilla. — Sepals 4 or 5, with an epicalyx ; petals 

 absent; stamens i — 4; aclienes' \ — 5. 



