In 1933, she attended summer classes and field trips on invertebrate zoology held by Professor S. F. Light at Moss Beach, just north of Half Moon Bay.
In the preface to the original edition, Light thanks Hartman for "contributing materially to this volume" and for "clarifying the classification of a group important in our fauna".
The lesson plan in the 1941 edition asks the students to refer to Hartman's thesis in the laboratory exercise dedicated to identifying Polychaeta.
Hartman received a Sarah Berliner Research Fellowship grant in 1939, allowing her to travel to study the annelid collections in Europe and the U.S. in preparation for a monograph on the subject.
[14] Naturalist Harry C. Yeatman recalls that Hartman once told director Prytherch "that her work on taxonomy ... of annelids was 'pure science' and had no practical value to mankind.
[15] She identified the culprit, a threat to oyster beds in Milford Harbor, Connecticut, as Polydora websteri, giving it a new name and description to differentiate it from P. caeca and P. ciliata.
Hartman's description and morphological illustrations helped contribute to an experiment testing whether the worms increased mortality in infected oysters.
[16] In 1966, Hartman published a comprehensive catalog of polychaetes in the Hawaii region based partly on data from historic expeditions in the early 20th century.
[17] Hartman moved to Los Angeles in 1940, and with a recommendation from Light, began working as a research associate for the Allan Hancock Foundation (AHF) at the University of Southern California (USC).
The results were influential for others engaged in the same research elsewhere and the sheer number of samples collected raised the status of the Polychaetes to that of a "dominant group of macroscopic benthic animals".
In 1983, the Southern California Association of Marine Invertebrate Taxonomists compiled these letters and began publishing them in their newsletter, primarily focusing on Hartman's travels and research throughout Europe in the early to mid-20th century, just before the outbreak of World War II.
[26] She writes about California wildflower season in April; an Allan Hancock Foundation Pacific expedition that encountered unusual indigenous people which baffled ethnologists; her colleagues who received fellowship grants like herself; and the impact of the worsening situation in Europe on her itinerary as she is just about to travel.
[28] In 1968, American biologist Joel Hedgpeth reviewed three volumes of Hartman's work on Antarctic polychaetes, calling it a "monumental achievement from the doyenne of polychaetology".
[29] In 1988, the University of Southern California transferred their polychaete collection from the Allan Hancock Foundation (AHF) to the Natural History Museum of Los Angeles County.
It contains the entirety of Hartman's Polychaeta library and her eastern Pacific specimens that she identified, which are considered part of the largest collection of worms of its kind.
[30] The Handbook of Zoology (2019) refers to Hartman's cataloging as "an amazing achievement and remarkably accurate given its ad hoc construction from original handwriting".