Corner started his career studying microfungi and published five papers on discomycetes. He then moved on to
nectriaceous fungi and was likely the first person to demonstrate the intimate relationship between fungi and
bryophytes. Further research regarding the fungal/bryophyte relationship has uncovered many more such associations, and researchers now estimate that more than 2000 exist. One of the qualities that made Corner such a remarkable scientist was his analytical skills; his legacy in mycology resides in the conclusions he was able to draw on fungal morphology and development as well as systematics. He also worked through the hyphal structure of
polypores with descriptions and illustrations of monomitic, dimitic and trimitic hyphal construction. He also made major strides in the systematics of
clavarioid fungi. As it stood in 1950, the genus
Clavaria was a polyphyletic assemblage of coral-shaped fungi. Corner determined that many species of "Clavaria" were actually members of different genera, families and even orders. Using spore characteristics, he determined that a genus of clavarioid fungi—
Ramaria—is closely related to a genus of cantharelloid fungi—
Gomphus. He also observed basidiospore development in boletoid and tricholomatoid fungi. In addition to working out systematic relationships of many groups of macrofungi, he also wrote monographs of large groups present in southeast Asia. His work on boletes led to the description of 123 new species and culminated in his classic monograph
Boletus in Malaysia as well as a supplement which included species in the genus
Phylloporus. Corner also wrote monographs on tricholomatoid, cantharelloid, clavarioid and polyporoid Corner's monographic work has not only aided those who work in tropical mycology but also those working on the groups in temperate ecosystems. Additionally, these monographs provide the framework for helping mycologists understand the extent of biodiversity in tropical ecosystems. Most of his collections, annotated books and illustrations are housed at the
Royal Botanic Garden Edinburgh. His other collections remain at Cambridge or at the United States National Fungus Collection in Beltsville, MD. ==Personal life==