Cobb earned his Ph.D. degree at the University of Jena in Germany in 1889 and was hired by the USDA in 1907. He was a leader in nematology research and trained the first generation of nematologists in the United States, making him the Father of Nematology in North America. His contributions included advances in understanding nematode anatomy and the description of more than 1,000 species. He developed sampling/extraction techniques and microscopic methods and in 1913 started the publication Contributions to a Science of Nematology. Cobb also was among the authors of the Plant Quarantine Act passed in 1912, stemming from the discovery of a root-knot nematode in a shipment of cherry trees gifted to the United States by the Japanese government in 1910.
(Submitted for publication in July 2008.)