In a plant herbarium, mostly to arrange plants, we make use of

Options

A. Hutchinson's system of classification
B. Bentham and Hookers system
C. Linnaeus system of classification
D. Haeckel system of classification

Answer

### Step-by-Step Solution:

1. **Understanding Plant Herbarium**: A plant herbarium is a collection or storehouse of preserved plant specimens. It serves as a reference for the identification and study of plant species.

2. **Preparation of Plant Specimens**: Before arranging the plants in a herbarium, the specimens must undergo specific preparation steps:
- **Drying**: Fresh plant specimens are dried to prevent decay.
- **Pressing**: The dried specimens are then pressed to flatten them and make them easier to store and display.
- **Preservation**: The pressed specimens are preserved to maintain their condition over time.

3. **Mounting the Specimens**: Once dried and pressed, the plant specimens are mounted on sheets of paper or other materials for display and study.

4. **Classification System**: The arrangement of these mounted plant specimens in a herbarium is based on a specific system of classification. The most commonly used system for this purpose is the **Bentham and Hooker system of classification**.

5. **Background of Bentham and Hooker**: This classification system was developed by two English taxonomists, George Bentham and Joseph Dalton Hooker. They published a comprehensive classification of the plant kingdom in their book titled "Genera Plantarum," which was released in three volumes between 1862 and 1883.

6. **Natural Classification**: The Bentham and Hooker system classifies plants based on their natural characteristics, which include morphological, anatomical, and reproductive features.

7. **Conclusion**: Therefore, in a plant herbarium, plants are primarily arranged using the Bentham and Hooker system of classification.

### Final Answer:
In a plant herbarium, mostly to arrange plants, we make use of the **Bentham and Hooker system of classification**.

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