Collaterial Gland
The ootheca in female cockroaches is secreted by the collaterial gland. This gland is responsible for producing the proteinaceous covering that protects the eggs and provides a suitable environment for the developing embryos.

Function of Collaterial Gland
The collaterial gland plays a crucial role in the reproductive process of female cockroaches. It secretes the substance that forms the ootheca, which serves as a protective covering for the eggs laid by the female. The ootheca also helps in retaining moisture and providing a safe environment for the developing embryos.

Structure of Ootheca
The ootheca is a proteinaceous capsule that contains the eggs of the cockroach. It is usually elongated and has a segmented appearance. The structure of the ootheca varies among different species of cockroaches, with some having smooth surfaces while others may have ridges or other features.

Importance of Ootheca
The ootheca is essential for the survival of cockroach offspring as it protects the eggs from desiccation, predators, and other environmental factors. It also ensures that the developing embryos receive the necessary nutrients and support for their growth and development.
In conclusion, the collaterial gland in female cockroaches is responsible for secreting the ootheca, which plays a vital role in protecting and nurturing the eggs laid by the female. This process is essential for the continuation of the cockroach species and the successful reproduction of these insects.