Which of the following structure is related to formation of middle layer of spermatophore in periplaneta?

Options

A. Utriculi majores
B. Utriculi breviores
C. Ejaculatory duct
D. Conglobate gland

Explanation

To answer the question regarding which structure is related to the formation of the middle layer of the spermatophore in Periplaneta (the cockroach), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Context**: Recognize that Periplaneta refers to the genus of cockroaches and that the spermatophore is a structure involved in their reproductive process. It is a bundle or pocket of sperm that is transferred during mating.

2. **Identify the Layers of the Spermatophore**: The spermatophore is composed of three layers. Each layer is formed by different structures of the cockroach's reproductive system.

3. **Determine the Layers**:
- **First Layer**: The first layer of the spermatophore is formed by the **Utriculus Majoris**, which is part of the mushroom gland.
- **Middle Layer**: The middle layer is formed by the **Ejaculatory Duct**.
- **Third Layer**: The third layer is formed by the **Conglobate Gland**.

4. **Answer the Question**: Since the question specifically asks for the structure related to the formation of the middle layer of the spermatophore, the correct answer is the **Ejaculatory Duct**.

5. **Select the Correct Option**: Based on the analysis, the answer is **Option C: Ejaculatory Duct**.

### Final Answer:
The structure related to the formation of the middle layer of the spermatophore in Periplaneta is the **Ejaculatory Duct**.

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