He wrote and lectured on domestic dogs, gardening, wildlife, wild flowers and trees.
Most of his writing was non-fiction, but in 1923 he also wrote an adventure short-story called The Bamboo Trap, about an American entomologist caught in a cave in the Ecuadorian jungle.
After finishing the Englewood School for Boys he studied at Yale University, where he earned a Bachelor of Arts degree in 1909.
In 1911, he accompanied a zoological expedition of the Academy of Natural Sciences of Philadelphia to Ecuador.
Lemmon travelled extensively throughout the United States and South America, where he studied the fauna and flora.