diff --git a/src/pyvalem/formula.py b/src/pyvalem/formula.py
index 034568e..5a6a3b1 100644
--- a/src/pyvalem/formula.py
+++ b/src/pyvalem/formula.py
@@ -315,6 +315,9 @@ def _parse_formula(self, formula):
         # photons, electrons, positrons and "M", denoting an unspecified
         # "third-body" in many reactions. Note that M does not have a defined
         # charge or mass.
+        if formula == "e":
+            # Quietly convert e to e-.
+            self.formula = formula = "e-"
         if formula in special_cases:
             for attr, val in special_cases[formula].items():
                 setattr(self, attr, val)
diff --git a/src/pyvalem/reaction.py b/src/pyvalem/reaction.py
index 4800cec..9c24f55 100644
--- a/src/pyvalem/reaction.py
+++ b/src/pyvalem/reaction.py
@@ -249,6 +249,7 @@ def _parse_species(self, lhs_str, rhs_str):
                             )
                     ss = StatefulSpecies(ss_str)
                     species.append((n, ss))
+                    ss_str = str(ss)
                     if ss_str not in species_map:
                         species_map[ss_str] = 0
                     species_map[ss_str] += n
diff --git a/tests/test_formula.py b/tests/test_formula.py
index a4ed070..2db2902 100644
--- a/tests/test_formula.py
+++ b/tests/test_formula.py
@@ -134,6 +134,7 @@ def test_special_formulas(self):
             ),
             "hv": ("hν", "hν", r"h\nu", "hv", 0, None, 0, {}),
         }
+        f["e"] = f["e-"]
         f["hν"] = f["hv"]
 
         for f_str in f:
diff --git a/tests/test_reaction.py b/tests/test_reaction.py
index 9247b3b..dd3d274 100644
--- a/tests/test_reaction.py
+++ b/tests/test_reaction.py
@@ -129,6 +129,8 @@ def test_reaction_equality(self):
             ],
             ["H + H + M -> H2 + M", "2H + M -> H2 + M"],
             ["Kr + hv -> Kr + 2hv", "Kr + hv -> Kr + hv + hv"],
+            ["Kr + hv -> Kr *", "Kr + hν -> Kr *"],
+            ["Kr + e- -> Kr- *", "Kr + e -> Kr- *"],
         ]
         for r1, r2 in equal:
             self.assertEqual(Reaction(r1), Reaction(r2))
@@ -186,14 +188,20 @@ def test_reaction_species_map(self):
         self.assertEqual(r.reactants_text_count_map, {"e-": 2, "C2": 1})
         self.assertEqual(r.products_text_count_map, {"C-": 2})
         r = Reaction("e- + e- + hv -> ", strict=False)
-        self.assertEqual(r.reactants_text_count_map, {"e-": 2, "hv": 1})
+        self.assertEqual(r.reactants_text_count_map, {"e-": 2, "hν": 1})
         self.assertEqual(r.products_text_count_map, {})
         r = Reaction("1e- + 1e- + 2hv -> ", strict=False)
-        self.assertEqual(r.reactants_text_count_map, {"e-": 2, "hv": 2})
+        self.assertEqual(r.reactants_text_count_map, {"e-": 2, "hν": 2})
         r = Reaction("e- + O2 X(3Σ-g) -> ", strict=False)
         self.assertEqual(r.reactants_text_count_map, {"e-": 1, "O2 X(3Σ-g)": 1})
         r = Reaction("e- + O2 X(3SIGMA-g) -> ", strict=False)
-        self.assertEqual(r.reactants_text_count_map, {"e-": 1, "O2 X(3SIGMA-g)": 1})
+        self.assertEqual(r.reactants_text_count_map, {"e-": 1, "O2 X(3Σ-g)": 1})
+
+    def test_reaction_with_e(self):
+        r = Reaction("e + C2 + e -> C- + C-")
+        self.assertEqual(r.reactants_text_count_map, {"e-": 2, "C2": 1})
+        self.assertEqual(r.products_text_count_map, {"C-": 2})
+        self.assertEqual(repr(r), "2e- + C2 → C- + C-")
 
 
 if __name__ == "__main__":