John Mawe (1764 - 1829) was a British mineralogist. Introduction To The Study Of Conchology: Describing The Orders, Genera, And Species Of Shells was published in 1825. John Mawe produced the first book giving a "how to" approach to the subject. Conchology is the study of shells of mollusks. It may also include the study of the exoskeletons of the phylum mollusca which include organisms where a trap door is present that the animal can use to protect itself from extreme conditions in the water and on land. The door is also used as a defense against enemies.