To view the PDF file, click on title of the paper. You will need a copy of Adobe Acrobat Reader and you will need to set up your web browser to automatically handle .PDF files. Take this into consideration before attempting to download them. Stockwell, S. A. 1989. Ph.D. Dissertation, University of California, Berkeley.
Emphasis is on the relationships among Recent genera, but major fossil groups are considered.
The position of the Scorpionida among the major chelicerates is also analyzed. All currently recognized non-buthid genera are incorporated into the analysis with some genera being further divided into subgenera or species groups. The Buthidae are treated only at the family level. Seven fossil groups at various taxonomic levels are also included. The Arachnida, Eurypterida, and Xiphosura are utilized as outgroups.