In Bentham and Hooker's system of classification the arrangement of three series of polypetalae reflects evolution from

Options

A. Bisexual to unisexuality
B. Dichlamydeous to monochlamydeous condition
C. Hypogyny to epigyny
D. Apocarpy to syncarpy.

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Classification System**: Bentham and Hooker developed a system of classification for flowering plants, particularly focusing on the arrangement of dicotyledons.

2. **Identifying the Groups**: In their classification, dicots were divided into three main groups:
- Polypetalae
- Gamopetalae
- Monochlamydeae

3. **Focusing on Polypetalae**: The question specifically asks about the arrangement of the three series within the Polypetalae group.

4. **Series of Polypetalae**: The Polypetalae are further divided into three series:
- **Series 1: Thalami Florae**: This series consists of hypogynous flowers.
- **Series 2: Dysi Florae**: This series consists of hypogynous flowers with a nectiferous disc.
- **Series 3: Chalciflorae**: This series includes flowers that are perigynous to epigynous.

5. **Understanding Flower Types**:
- **Hypogynous flowers**: The ovary is situated above the other floral parts.
- **Perigynous flowers**: The ovary is surrounded by the other floral parts at the same level.
- **Epigynous flowers**: The ovary is situated below the other floral parts.

6. **Evolutionary Reflection**: The arrangement of these series reflects an evolutionary trend from hypogynous flowers (Series 1) through to perigynous flowers (Series 3), culminating in epigynous flowers.

7. **Conclusion**: Therefore, in Bentham and Hooker's system of classification, the arrangement of the three series of Polypetalae reflects evolution from hypogyny to epigyny.

**Final Answer**: The arrangement of three series of Polypetalae reflects evolution from hypogyny to epigyny.

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