(Rewrites first paragraph; adds CEO comment, byline)

By Jonathan Stempel

NEW YORK (Reuters) - Jefferies Group Inc (JEF.N: Quote, Profile, Research), an investment bank that serves mid-sized companies, said on Monday that it would sell a 13.7 percent stake to Leucadia National Corp (LUK.N: Quote, Profile, Research), raising $434 million of equity capital following its second straight quarterly loss.

Leucadia will buy 26.59 million shares, inject $100 million of cash, and take two newly created seats on Jefferies' board, which now has seven members. Jefferies said it will buy 10 million Leucadia shares and pay $100 million cash. Both companies are based in New York.

Jefferies also reported a first-quarter loss of $60.5 million, or 43 cents per share, compared with a year-earlier profit of $62.3 million, or 42 cents a share. Net revenue fell 52 percent to $201.2 million.

Analysts on average had expected a profit of 14 cents per share on revenue of $345.5 million, according to Reuters Estimates.

Jefferies joins a growing list of financial companies to raise outside capital since the global credit crisis began last summer. The crisis has caused industrywide investment banking results to slump and credit and trading losses to mount.

"So why did we just raise $434 million?" Chief Executive Richard Handler said on a conference call. "The first quarter of 2008 was the most brutal environment we have ever seen. The liquidity crisis and panic that has spread around the globe has devastated financial institutions everywhere."

Leucadia is a holding company engaged in several businesses, and also takes equity stakes in other companies.