<?xml version="1.0" encoding="us-ascii"?>
<!--XBRL document created by RR Donnelley IM Processor 5.0.0.0 using Fujitsu Interstage XWand-->
<schema targetNamespace="http://www.leggmason.com/20121128" elementFormDefault="qualified" xmlns="http://www.w3.org/2001/XMLSchema" xmlns:lmpit32="http://www.leggmason.com/20121128" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:nonnum="http://www.xbrl.org/dtr/type/non-numeric">
  <annotation>
    <appinfo>
      <link:linkbaseRef xlink:type="simple" xlink:href="lmpit32-20121128_pre.xml" xlink:title="Presentation Links, all" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="lmpit32-20121128_cal.xml" xlink:title="Calculation Links, all" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="lmpit32-20121128_def.xml" xlink:title="Definition Links, all" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:linkbaseRef xlink:type="simple" xlink:href="lmpit32-20121128_lab.xml" xlink:title="Label Links, all" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
      <link:roleType roleURI="http://www.leggmason.com/role/DocumentDocumentandEntityInformation" id="DocumentDocumentandEntityInformation">
        <link:definition>000000 - Document - Document and Entity Information</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.leggmason.com/role/DocumentRiskReturnSummaryUnlabeledLeggMasonClearBridgeSmallCapGrowthFund" id="DocumentRiskReturnSummaryUnlabeledLeggMasonClearBridgeSmallCapGrowthFund">
        <link:definition>000011 - Document - Risk/Return Summary {Unlabeled} - Legg Mason ClearBridge Small Cap Growth Fund</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.leggmason.com/role/ScheduleShareholderFeesLeggMasonClearBridgeSmallCapGrowthFund" id="ScheduleShareholderFeesLeggMasonClearBridgeSmallCapGrowthFund">
        <link:definition>000012 - Schedule - Shareholder Fees {- Legg Mason ClearBridge Small Cap Growth Fund}</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.leggmason.com/role/ScheduleAnnualFundOperatingExpensesLeggMasonClearBridgeSmallCapGrowthFund" id="ScheduleAnnualFundOperatingExpensesLeggMasonClearBridgeSmallCapGrowthFund">
        <link:definition>000013 - Schedule - Annual Fund Operating Expenses {- Legg Mason ClearBridge Small Cap Growth Fund}</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.leggmason.com/role/ScheduleExpenseExampleTransposedLeggMasonClearBridgeSmallCapGrowthFund" id="ScheduleExpenseExampleTransposedLeggMasonClearBridgeSmallCapGrowthFund">
        <link:definition>000014 - Schedule - Expense Example {Transposed} {- Legg Mason ClearBridge Small Cap Growth Fund}</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.leggmason.com/role/ScheduleExpenseExampleNoRedemptionTransposedLeggMasonClearBridgeSmallCapGrowthFund" id="ScheduleExpenseExampleNoRedemptionTransposedLeggMasonClearBridgeSmallCapGrowthFund">
        <link:definition>000015 - Schedule - Expense Example, No Redemption {Transposed} {- Legg Mason ClearBridge Small Cap Growth Fund}</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.leggmason.com/role/ScheduleAnnualTotalReturnsLeggMasonClearBridgeSmallCapGrowthFundBarChart" id="ScheduleAnnualTotalReturnsLeggMasonClearBridgeSmallCapGrowthFundBarChart">
        <link:definition>000016 - Schedule - Annual Total Returns - Legg Mason ClearBridge Small Cap Growth Fund [BarChart]</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.leggmason.com/role/ScheduleAverageAnnualTotalReturnsTransposedLeggMasonClearBridgeSmallCapGrowthFund" id="ScheduleAverageAnnualTotalReturnsTransposedLeggMasonClearBridgeSmallCapGrowthFund">
        <link:definition>000017 - Schedule - Average Annual Total Returns {Transposed} {- Legg Mason ClearBridge Small Cap Growth Fund}</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.leggmason.com/role/DocumentRiskReturnDetailUnlabeledLeggMasonClearBridgeSmallCapGrowthFund" id="DocumentRiskReturnDetailUnlabeledLeggMasonClearBridgeSmallCapGrowthFund">
        <link:definition>000018 - Document - Risk/Return Detail {Unlabeled} - Legg Mason ClearBridge Small Cap Growth Fund</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.leggmason.com/role/DisclosureRiskReturnDetailDataElementsLeggMasonClearBridgeSmallCapGrowthFund" id="DisclosureRiskReturnDetailDataElementsLeggMasonClearBridgeSmallCapGrowthFund">
        <link:definition>000019 - Disclosure - Risk/Return Detail Data {Elements} - Legg Mason ClearBridge Small Cap Growth Fund</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.leggmason.com/role/DocumentRiskReturnSupplementUnlabeledLeggMasonClearBridgeSmallCapGrowthFund" id="DocumentRiskReturnSupplementUnlabeledLeggMasonClearBridgeSmallCapGrowthFund">
        <link:definition>000010 - Document - Risk/Return Supplement {Unlabeled} - Legg Mason ClearBridge Small Cap Growth Fund</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
    </appinfo>
  </annotation>
  <import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" />
  <import namespace="http://xbrl.sec.gov/dei/2012-01-31" schemaLocation="http://xbrl.sec.gov/dei/2012/dei-2012-01-31.xsd" />
  <import namespace="http://xbrl.sec.gov/rr/2012-01-31" schemaLocation="http://xbrl.sec.gov/rr/2012/rr-2012-01-31.xsd" />
  <import namespace="http://www.xbrl.org/dtr/type/non-numeric" schemaLocation="http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd" />
  <element name="S000016663Member" id="lmpit32_S000016663Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <element name="C000046572Member" id="lmpit32_C000046572Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <element name="C000046565Member" id="lmpit32_C000046565Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <element name="C000046566Member" id="lmpit32_C000046566Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <element name="C000046567Member" id="lmpit32_C000046567Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <element name="C000046569Member" id="lmpit32_C000046569Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <element name="C000046571Member" id="lmpit32_C000046571Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <element name="C000063670Member" id="lmpit32_C000063670Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <element name="C000046568Member" id="lmpit32_C000046568Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <element name="C000046570Member" id="lmpit32_C000046570Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <element name="C000076731Member" id="lmpit32_C000076731Member" type="nonnum:domainItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <element name="SupplementTextBlock" id="lmpit32_SupplementTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
</schema>
