1 Exhibit 23.7 CONSENT OF ALLEN C. EWING & CO. We hereby consent to the inclusion as Appendix C to the Proxy Statement-Prospectus constituting part of the Registration Statement on Form S-4 of F.N.B. Corporation of our letter to the Board of Directors of Indian Rocks State Bank and to the references made to such letter and to the firm in the Proxy Statement-Prospectus. ALLEN C. EWING & CO. By: /s/ Charles E. Harris ------------------------------------------- Charles E. Harris President and Chief Executive Officer Orlando, Florida July 28, 1997