This scientic illustration is one of many that were created by Orra White Hitchcock for use by Edward Hitchcock in his lectures at Amherst College. The subjects of the classroom charts ranged from views of geological strata and maps to images of fossil tracks and prehistoric skeletons. The illustrations were one of the many ways in which Orra supported her husband's scientific endeavors. Edward saw these classroom tools as invaluable to himself, to his students, and to the institution at which he taught. He wrote:
"These drawings and paintings cover many thousand square feet of surface, and illustrate the principles of Botany, Geology, Zoology and Anatomy. The college has never had any funds which it could devote to procure these indispensable aids to the lecturer. But Mrs. H. has been steadily at work for thirty-six years, whenever called upon, to supply my numerous demands, and that, too, without the slightest pecuniary compensation, or the hope of artistic reputation . . . [they] may be looked upon as her donation to the college; while to myself, money would poorly represent my indebtedness, since without this aid, I never could have intelligibly explained, or given any interest to the subjects of my lectures."