11.   BonusMail is offered through Internet service providers such as Prodigy, Concentric and Erols, and through the on-line directory assistance service, WhoWhere?

12.   But no one disputes that the quality of directory assistance service varies from provider to provider.

13.   CBS introduced an Internet portal Tuesday, modeled after Yahoo and other directory services that are the most popular sites on the World Wide Web.

14.   For example, Wolfe Tech Pocket Genie is an optional service that gives you all kinds of on-demand information, including phone directory services and driving directions.

15.   It has also been difficult for computer telephone callers to locate each other without inconvenient and sometimes costly third-party directory services.

16.   Infoseek is the third most popular search and directory service behind Excite and top-ranked Yahoo.

17.   Its links include nine Web sites that offer no-cost directory assistance services.

18.   Lacking an official electronic phone book, directory services must scrape together their own lists from old phone listings, real-estate records and similarly obscure databases.

19.   Lycos, which is based in Marlboro, Mass., is the first of three Internet directory services scheduled to go public this month.

20.   Netscape also derives significant revenue from its site on the World Wide Web, Netcenter, which offers directory services and sells advertising.