STAMFORD, Conn. (AP) _ Xerox Corp. announced Tuesday that its second-quarter income rose 35 percent from the same period a year ago, mostly because of an increase in sales of copiers and a turnaround at its Crum & Forster insurance subsidiary.

The company reported net income from continuing operations of $118 million, or $1.11 per share, compared with $88 million, or 79 cents per share, in the same period of 1984.

Revenue in the quarter was $2.14 billion, up 3 percent from $2.1 billion in the first three months of last year.

For the first six months, the Stamford-based company reported net income from continuing operations of $234 million, or $2.19 per share, on revenue of $4.09 billion. In the comparable period of 1984, Xerox earned $222 million, $2.07 a share, on revenues of $4.02 billion.

Included in second-quarter income was a one-time $16 million gain from a U.S. tax settlement. In 1984's second-quarter, the company included a one-time $9 million gain from a debt-to-equity swap.

Speaking to analysts gathered at the company's headquarters here, Xerox Chairman and Chief Executive Officer David T. Kearns said he was ''generally pleased'' with the results, which he said showed that the company is ''on track'' for the ''solid 1985'' he first predicted in January.

Among the highlights of the second-quarter figures, analysts said, was the profitablility of Crum & Forster, which lost $15 million a year ago. During the second quarter of this year, it produced income of $4 million.

Kearns said the turnaround was achieved through increases in prices, tighter underwriting standards, a reduction in less productive agents and the closing of several offices.

Some analysts at the meeting showed concern that Crum & Forster's earned premiums increased at a slower pace than much of the property and casualty insurance industry. But Melvin Howard, preisdent of the Xerox financial operation, said that was expected, however, as ''we have taken this opportunity to get our house in order. We're cleaning up at a time when we feel we can.''

Kearns said that ''despite a difficult business climate'' marked by low prices and stiff foreign competition - particularly in its middle-priced lines - sales of photocopiers and duplication equipment rose about 12 percent in the second quarter from the same period a year ago. The company's 10-series of copiers now represent about one-third of placements, he said.

The 10-series was introduced in September 1982.

Xerox results do not reflect the performance of discontinued operations, which would have contributed $103 million, or $1.06 per share, to second- quarter earnings. Of that $103 million, $95 million was derived from the sale of three of its publishing subsidiaries.

The company chose to isolate not only the three businesses sold but three additional ones it hopes to sell by the end of the year. Including the discontinued operations, Xerox income in the second quarter was $221 million, or $2.17 per share.

The company announced in April that it would sell its vast publishing businesses: AutEx Systems, Ginn & Co., Xerox Learning Systems, University Microfilms International, Xerox Education Systems and R.R. Bowker. The sale of AutEx, Ginn & Co. and Xerox Learning Systems generated $95 million.

Negotiations are under way for the sale of the other three. Xerox hopes to realize $500 million from the sale of all of its publishing holdings, Kearns said.

He said the company decided to sell the companies ''because it became clear that a greater financial commitment would be required if we were to grow those businesses enough to be competitive. We would have needed to divert resources from our other operations.''

During the second quarter, Xerox announced a major push into the office automation market with the introduction of new word processors, laser printers, an enhanced version of the company's unsuccessful personal computer and a host of affiliated software.

Most of the new products sold are scheduled for delivery to customers in the third quarter, Kearns said.

Eugene Glazer, an analyst with Dean, Witter Reynolds, said Xerox has been hurt by declining prices in its photocopier and office-equipment markets, as well as the foreign competition.

''They've improved their own product line and are better servicing their customers, but the environment is difficult,'' Glazer said.

He said the company's entry into office automation came at an unfortunate but necessary time, given the slump in the nation's computer industry.

''They've got to get in early to show a commitment before their customers go elsewhere,'' he said. ''They have to show their cards even though the products aren't there yet.''