Which of the following is not correctly matched :–

Options

A. Heterocyst = `N_2`-fixation structure of B.G.A.
B. Hormogonia = Reproductive structure of B.G.A
C. Floridean starch = Stored food of brown algae
D. Cyanophycean starch = Stored food of B.G.A.

Answer

To solve the question "Which of the following is not correctly matched?", we will analyze each option provided.

### Step-by-Step Solution:

1. **Analyze Option 1: Heterocyst**
- Heterocysts are specialized cells found in certain cyanobacteria (blue-green algae) that are involved in nitrogen fixation.
- **Conclusion**: This option is correctly matched.

2. **Analyze Option 2: Hormogonia**
- Hormogonia are motile filaments that are formed by some cyanobacteria and are involved in vegetative reproduction.
- **Conclusion**: This option is also correctly matched.

3. **Analyze Option 3: Floridian Starch**
- Floridian starch is the stored food in red algae (rhodophytes), not brown algae.
- **Conclusion**: This option is incorrectly matched.

4. **Analyze Option 4: Cyanophycine Starch**
- Cyanophycine starch is indeed the stored food of blue-green algae (cyanobacteria).
- **Conclusion**: This option is correctly matched.

### Final Answer:
The option that is not correctly matched is **Option 3: Floridian starch and brown algae**.

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