In the garden, earthworm can be traced by their faecal deposits known as-

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the name of the fecal deposits left by earthworms in the garden.

2. **Identifying Earthworm Activity**: Earthworms are known for their role in soil aeration and nutrient cycling. As they move through the soil, they excrete waste.

3. **Recognizing Fecal Deposits**: The waste produced by earthworms is not just any waste; it plays a significant role in enriching the soil.

4. **Naming the Fecal Deposits**: The fecal deposits left by earthworms are specifically referred to as "worm castings."

5. **Understanding the Importance**: Worm castings are beneficial for soil fertility, as they improve soil structure and provide essential nutrients for plant growth.

6. **Conclusion**: Therefore, the fecal deposits of earthworms in the garden are known as "worm castings."

**Final Answer**: Worm castings.

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