**Answer:**

Spread footings are a type of foundation used to distribute the load of a structure over a larger area of soil. They are designed to prevent excessive settlement or instability of the structure. Among the options provided, the **Inverted Arch footing** is not a type of spread footing. The other three options, **Wall footings, Grillage footings, and Caisson footings,** are all examples of spread footings.

**1. Inverted Arch footing:**
An inverted arch footing is a special type of foundation used in certain circumstances where the soil beneath the structure is weak or has low bearing capacity. It is designed to transfer the load of the structure to deeper, more competent layers of soil or rock. Unlike spread footings, which distribute the load over a larger area, the inverted arch footing concentrates the load at specific points or areas where the soil can safely support it.

**2. Wall footings:**
Wall footings, also known as strip footings, are a common type of spread footing used to support load-bearing walls. They are long and narrow in shape, extending the full length of the wall they are supporting. Wall footings distribute the load of the wall over a larger area of soil, preventing excessive settlement and ensuring stability.

**3. Grillage footings:**
Grillage footings are a type of spread footing used to support heavy structural loads, such as those from columns or piers. They consist of a horizontal grillage, which is a framework of steel beams or concrete slabs, supported by multiple vertical piles or columns. The grillage distributes the load from the columns or piers over a larger area, reducing the pressure on the underlying soil.

**4. Caisson footings:**
Caisson footings, also known as drilled shafts or piers, are another type of spread footing used to support heavy loads. They are cylindrical or rectangular structures that are drilled or excavated into the ground and filled with concrete or reinforced with steel. Caisson footings transfer the load of the structure to deeper, more stable layers of soil or rock.

In summary, while all of the options provided are types of footings, the inverted arch footing is not a spread footing. The other options, including wall footings, grillage footings, and caisson footings, are examples of spread footings commonly used in construction.