Twitter: Strange Bedfellows Fund Microblogger

Twitter’s pending cash infusion comes in part from a Wall Street giant and another firm known more for retirement investing than venture capitalism.

Twitter has confirmed a new fundraising round, although without disclosing the amount, which reports have pegged at $100 million for a $1 billion valuation.

Investment bank Morgan Stanley and T. Rowe Price are among the high-dollar contributors. Morgan Stanley alone is said to have paid just a little less than $10 million. Writers at the Business Insider said that means Morgan Stanley “just bought itself the Twitter IPO!”

Meanwhile, it’s unclear what T. Rowe Price is doing in the mix. The retirement funds company has only funded seven start-up deals in four years, according to the Wall Street Journal, and only one was related to the Internet. A T. Rowe Price spokeswoman wouldn’t comment to the Journal about the company’s rationale for investing in Twitter.