"Since I was nine years old, I've aspired to study mycology, and have met many different people along the way. I have struggled through hard times, never stopping my work, but at age 63, I am still no closer to knowing whether my work will bear fruit or not".

After returning to Wakayama, Kumagusu immersed himself in collecting specimens from the forests of Nachi. At the end of 1905, he sent 47 specimens to the cryptogamic plant research division of the Biritsh Museum. A man named Murray had been the one to suggest he study cryptogamic plants, but by the time Kumagusu sent them he had already left the Museum. Luckily, the specimens were passed on to the world’s most influential person in the study of slime molds, Arthur Lister. Lister found Kumagusu’s specimens to be very valuable, so they struck up a correspondence. Over time, Kumagusu sent him 450 different samples, 10 of which were announced to be of a new genus or a new species. Lister even named one kind of slime mold found on the trunk of a persimmon tree in Kumagusu’s garden after him: “Minakatella longifila”.

Kumagusu aspired to collect a specimen of every kind of slime mold that existed in Japan. In 1927, he released a catalogue of every known type, which included 196 varieties. At the time, there were only 300 varieties known throughout the world, so Kumagusu’s dedication to the field was truly amazing.