diff --git a/include/cantera/oneD/Inlet1D.h b/include/cantera/oneD/Inlet1D.h
index 3a77777eb..e85ad4cce 100644
--- a/include/cantera/oneD/Inlet1D.h
+++ b/include/cantera/oneD/Inlet1D.h
@@ -58,6 +58,8 @@ public:
         return m_temp;
     }
 
+    virtual size_t nSpecies() { return 0; }
+
     /// Set the mole fractions by specifying a std::string.
     virtual void setMoleFractions(const std::string& xin) {
         err("setMoleFractions");
@@ -169,6 +171,8 @@ public:
 
     virtual void _finalize(const doublereal* x) {}
 
+    virtual size_t nSpecies() { return m_nsp; }
+
     virtual void setMoleFractions(const std::string& xin);
     virtual void setMoleFractions(doublereal* xin);
     virtual doublereal massFraction(size_t k) {
@@ -319,6 +323,8 @@ public:
         ;
     }
 
+    virtual size_t nSpecies() { return m_nsp; }
+
     virtual void setMoleFractions(const std::string& xin);
     virtual void setMoleFractions(doublereal* xin);
     virtual doublereal massFraction(size_t k) {