메꽃과 Convolvulaceae
1. 기생식물로서 수술 밑에 인편이 있다 ··········································································································
새삼속
1. 독립영양식물로서 수술 밑에 인편이 없다.
2. 암술머리는
얕거나 또는 깊게 2 개로 갈라진다 ····················································································155. 아욱메풀
2. 암술머리는
갈라지지 않는다 ·················································································································
메꽃속
3. 암·수술은 꽃안에 들어있다.
4. 꽃받침잎은
혁질이며 끝이 뾰족하고 씨방은 대개 3실이다 ······································································ 나팔꽃속
4. 꽃받침잎은
막질 또는 혁질이고 끝이 둔하거나 뾰족하고 씨방은 2-4실이다 ············································· 158. 고구마
3. 암·수술은 꽃밖으로 나와있다 ··········································································································
유홍초속