The Harvard Trust Co., which had no Negro tellers at the beginning of July, has hired three during the last four months.

In July, the Congress of Racial Equality (CORE) was reported to be considering an investigation of the bank's hiring practices. At the time, Herbert M. Allen, a vice-president of the company, expressed surprise at CORE's plans, saying that "we don't discriminate against Negroes."

Theodore Cook, personnel director of the Harvard Trust, yesterday attributed the recent hiring of the Negroes to a substantial rise in the number of Negro applicants.

In the past, Cook added, the bank has always "held out for a type of person who would be a good representative of his race in this type of job." "We have always felt," Cook said, "that we did not want to just hire someone simply because he was a Negro."

The recent hiring was not the result of any pressure on the part of CORE, Cook said. It was done on the bank's initiative, he explained, because the company has "recognized the reality of the fact they won't get the ideal Negro."

Alan Gartner, chairman of the greater Boston chapter of CORE, said that the increase in the number of Negro applicants to the bank has probably been caused indirectly by CORE's work with banks in the Boston area. CORE is currently negotiating with three Boston banks and has made appreciable progress with two of them, according to Gartner.

The example set by these two banks has probably influenced the policy of the Harvard Trust, Gartner said. He added that it seems also to have influenced the attitudes of prospective employees.

"When a company indicates with deeds instead of words, that it is willing to hire Negroes," other Negroes are encouraged to apply for jobs, Gartner explained.