WATERVILLE — Flags at Colby College were lowered to half-staff Wednesday in memory of a retired art professor who drowned with his daughter while they were vacationing off the coast of Puerto Rico.

The bodies of James M. Carpenter, 78, a Waterville resident who founded Colby’s art department, and his daughter, Jane Poliquin, 40, of Cumberland Foreside, were found Tuesday night in Candelero Beach in Humacao, Puerto Rico, police said.

The two were staying at the Palmas del Mar resort in Humacao and had been seen walking toward the beach at about noon Tuesday, police said.

Doctors at a local hospital certified that the cause of death was drowning. District Attorney Alberic Prados Bou ordered the bodies transferred to the Institute of Forensic Medicine for autopsies.

Police were investigating the cause of the drownings.

Carpenter, a native of Glens Falls, N.Y., had been a professor emeritus since retiring from Colby in 1981 after 31 years on the faculty. He previously taught at Harvard, where he held bachelor’s and doctorate degrees.

Carpenter is credited as the founder of the college’s art department, which now has a dozen faculty members. He also was the moving force behind Colby’s art museum and served as its first director, from 1959 to 1966.

A painter and art historian, Carpenter was remembered by colleagues as a gentle but determined man who was generous with his time and knowledge.

“He had a really profound impact on the students,” said Hugh Gourley, whom Carpenter hired in 1966 to replace him as director of the art museum.

Because of Carpenter’s influence, Gourley said, “many students followed art as their profession.”

William B. Miller, a retired art professor, said Carpenter “was one of the people I admired very much. I think he was admired by many generations of students.”