The book is based on a series of lectures on the Acari, one of the largest and biologically most diverse groups of the Arachnida, and provides a detailed introduction to the group, concentrating on their functional morphology, but also covering classification and economic importance. It is intended as a text and reference book for acarologists and advanced students taking courses in general entomology (traditionally including acarology), invertebrate zoology, and agricultural, medical and veterinary entomology. The book contains an introduction describing the preparation of material for microscopic study, followed by chapters covering: integument and moulting; segmentation, musculature and legs; circulation, nervous system and sense organs; respiratory systems; mouthparts; feeding and adaptation of the mouthparts; alimentary canal, prosomatic glands and digestion; excretion and osmoregulation; reproductive systems; methods of sperm transfer, mating behaviour and oviposition; development and dispersal; and classification. Taxonomic and subject indexes are included.