Which of the following statements is incorrect w.r.t. reproductive system of earthworm?

Options

A. There are two pairs of testes present in 10th and 11th segments. Their ducts i.e., vas deferens run upto the 18th segment where they join the prostatic duct
B. Accessory glands are present on the ventral side of the 17th and 19th segments.
C. One pair of ovaries is attached at the intersegmental septum of the 13th and 14th segments
D. Four pairs of sac like structures called spermathecae are found one pair each in 6th to 9th segments

Explanation

To determine which statement is incorrect regarding the reproductive system of the earthworm, we will analyze each statement provided in the question.

### Step-by-Step Solution:

1. **Statement Analysis**:
- **Statement 1**: "There are two pairs of testes which lie in the 10th and the 11th segment and their ducts has vast difference which runs up to the 18th segment where they join the prostatic duct."
- **Analysis**: This statement is correct. The testes are indeed located in the 10th and 11th segments, and their ducts extend to the 18th segment to connect with the prostatic duct.

2. **Statement 2**: "The accessory glands are present on the ventral side of the 17th and the 19th segment."
- **Analysis**: This statement is also correct. The accessory glands are located in the 17th and 19th segments and open ventrolaterally through ducts on the genital papilla.

3. **Statement 3**: "One pair of ovaries attached to the intersegmental septum of 13th and the 14th one."
- **Analysis**: This statement is incorrect. The ovaries are actually attached to the posterior surface of the septum between the 12th and 13th segments, not the 13th and 14th segments.

4. **Statement 4**: "Four pairs of satellite structures per methecae lie one in each pair in the intersegmental groups between the 6th to 9th segment."
- **Analysis**: This statement is correct. The satellite structures are indeed located in the intersegmental groups between the 6th to 9th segments.

5. **Conclusion**: Based on the analysis, the incorrect statement regarding the reproductive system of the earthworm is **Statement 3**.

### Final Answer:
The incorrect statement with respect to the reproductive system of the earthworm is: **"One pair of ovaries attached to the intersegmental septum of 13th and the 14th one."**

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