11. Later he specialised in conchology , especially that of the West Coast of the United States. 12. He distinguished himself in his studies and showed an interest in natural history, conchology and geology. 13. This training, and his interest in conchology , set him on his life's work. 14. Shell sizes are given in millimetres and recorded to the nearest, as is standard in conchology . 15. Henry also followed his father's interest in natural history and wrote several papers on descriptive conchology . 16. He commenced in practice at Swansea, but devoted his leisure time to natural history, especially conchology . 17. Both the science of studying mollusk shells and the hobby of collecting and classifying them are known as conchology . 18. Banks introduced him to William Elford Leach a curator at the British Museum . He studied conchology with Leach. 19. Thereafter, Pilsbry continued as editor of the ongoing multi-volume " Manual of Conchology ". 20. In the fields of conchology and palaeontology, he conducted collecting expeditions to the Pyrenees, Catalonia and Italy.
