8o Cornaceae, Pirolaceae 



Fam. 3. Cornaceae. Trees or shrubs. Leaves 

 opposite or spiral, usually entire, exstipulate. Flowers 

 small, in cymes, umbels, or heads, 4-5-merous, mostly 

 haplostemonous. Carpels (4-1) with an epigynous disc, 

 each carpel with one ovule. Micropyle facing outwards 

 or inwards. Style i. Fruit a drupe or berry. 



Subfamily Cornoideae. Ovary inferior. Raphe 

 dorsal. 



Only British genus (leaves opposite. Petals 4, val- 

 vate) : Cornus. 



Subclass 2. METACHLAMYDEAE (Sympe- 

 talae). Perianth in advanced stage of development, 

 always originally double, and the inner whorl gamo- 

 petalous. Polypetalous forms occur but they are closely 

 related to gamopetalous forms. 



A. Polypetaly, as well as sympetaly, occurs. 

 Two whorls or one whorl of stamens. Hypogyny 

 predominates, but epigyny also occurs. (For B 

 see page 85.) 



Order i. Ericales. Shrubs and herbs, rarely trees, 

 with simple leaves. Flowers 4-5-merous, obdiplostemo- 

 nous, or the antipetalous whorl of stamens not developed. 

 Petals free or united. Stamens hypogynous or epigy- 

 nous, more rarely united at base with the petals. Carpels 

 (2-00 ), when isomerous opposite petals. Ovary superior 

 or inferior. Ovules with one integument. 



Fam. I. Pirolaceae. Evergreen or colourless 

 perennial herbs with spiral leaves. Flowers solitary 

 or racemose, 5-4-merous, obdiplostemonous. Petals 

 free or united. Stainens hypogynous. Carpels (5-4) 

 each with 00 minute ovules on fleshy placentae. Capsule 



