Hermann August Hagen was a German entomologist who specialised in Neuroptera and Odonata.
Background
Hagen was the son of Carl Heinrich Hagen and Anna (Linck) Hagen. His father was professor of political economy, technology and agriculture at the University of Königsberg, and his grandfather, Carl Gottfried Hagen, had been professor of natural history there.
Education
Young Hagen graduated from the gymnasium in 1836, and in 1839 published his first paper on dragonflies of East Prussia. He then studied medicine in Berlin, Vienna, Paris, and elsewhere.
Career
In 1845 he began to collaborate with Edmond de Sélys Longchamps. He toured major entomological collections and libraries in Norway, Sweden, Denmark and Germany with zoology professor Martin Heinrich Rathke in 1839. In 1840, he received his medical degree from the University of Königsberg, having written his thesis on European species of dragonflies.
In 1843, he returned to Königsberg, entered on the general practice of medicine, and for three years was first assistant at the surgical hospital.
During this time, he continued his entomological studies. In 1856 he met a Russian entomologist, Karl Robert Osten-Sacken, who brought American neuropteroid insects to his attention.
While holding these civic offices, he was invited by Louis Agassiz to come to Cambridge as assistant in entomology at the Museum of Comparative Zoology at Harvard. Agassiz had been encouraged in this idea by Osten-Sacken.
Hagen accepted, and in 1867 he emigrated to the United States of America.
He developed the department of entomology at Harvard, and in 1870 was made professor of that science, being the first professor of entomology in an American university. He founded the Cambridge Entomological Club. In 1863, he received the honorary degree of Doctor of Philosophy from the University of Königsberg.
In 1882, he traveled to Montana, California, Oregon and Washington where he collected harmful insects.
His transcript for taxonomic descriptions is “Hag.”.
Membership
German Academy of Sciences Leopoldina]
From 1863 until 1867, he was vice president of the city council and a member of the school board in Königsberg. He was a member of several scientific societies including the American Academy of Arts and Sciences, the American Philosophical Society and the American Entomological Society.