Herman J. Melish is a scientist. He appears in the episode "Son of Return of the Fly II" of the 1987-1996 animated series, and develops a solid energy generator crystal, for which he is chased by two men. The Turtles rescue him from the men, but the generator falls into the sewer and Melish begs them to retrieve it.
At the end of the episode he appears at Channel 6, asking if the Turtles have retrieved the device. He then confirms that the device has a self-destruct button that he had all along, but that he didn't use it because he wants to make a profit from it. His efforts come to nothing, since Leonardo destroyed his device anyway.