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    <periodOfReport>2025-06-01</periodOfReport>

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    <issuer>
        <issuerCik>0000740663</issuerCik>
        <issuerName>FIRST OF LONG ISLAND CORP</issuerName>
        <issuerTradingSymbol>FLIC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001637639</rptOwnerCik>
            <rptOwnerName>HILTON CHRISTOPHER J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>275 BROADHOLLOW ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MELVILLE</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>11747</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
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            <isOfficer>1</isOfficer>
            <officerTitle>SEVP</officerTitle>
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    <footnotes>
        <footnote id="F1">Pursuant to the Agreement and Plan of Merger, dated as of September 4, 2024 (the &quot;Merger Agreement&quot;), between the Issuer and ConnectOne Bancorp, Inc., each issued and outstanding share of Issuer common stock was converted into the right to receive 0.5175 shares of ConnectOne Bancorp, Inc. common stock (subject to the payment of cash in lieu of fractional shares) (the &quot;Per Share Stock Consideration&quot;).</footnote>
        <footnote id="F2">Represents performance-based restricted stock units (&quot;PSUs&quot;) which were originally granted on January 1, 2024, but have not been previously reported. At the Effective Time of the merger (as defined in the Merger Agreement), pursuant to the terms of the Merger Agreement, the PSUs vested at target level and were exchanged for the Per Share Stock Consideration.</footnote>
        <footnote id="F3">At the Effective Time of the merger (as defined in the Merger Agreement), pursuant to the terms of the Merger Agreement, each unvested Restricted Stock Unit fully vested and was exchanged for the Per Share Stock Consideration.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Maria Doyle, pursuant to power of attorney</signatureName>
        <signatureDate>2025-06-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
