The Arachnology reference article from the English Wikipedia on 24-Apr-2004
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Arachnology

Helping orphans the way you would do it
Arachnology is the scientific study of spiders and related organisms such as scorpions, pseudoscorpions, harvestmen. However, the study of ticks and mites is usually not included in arachnology, but is called Acarology.

See also: Entomology