This book combines the knowledge assembled in two publications, published in the journal Colligo, describing the type specimens of land snails collected from the island groups of the Azores, Madeira, the Canary Islands, and Cape Verde:
- Oliver, G., Groh, K. & Ismail, L.: Type specimens of Macaronesian land snails described by R. T. Lowe held in the Booth Museum, Brighton - A forgotten taxonomic resource.
- Oliver, G. et al.: Recognised Type Specimens in a Dispersed Collection. The Macaronesian Land Mollusca Described by R. T. Lowe.