diff --git a/polyrat/arnoldi.py b/polyrat/arnoldi.py
index f2755e9..76d4f5e 100644
--- a/polyrat/arnoldi.py
+++ b/polyrat/arnoldi.py
@@ -185,7 +185,7 @@ def vandermonde(self, X, weight = None):
 
 	def vandermonde_derivative(self, X, weight = None):
 		if np.array_equal(X, self.X):
-			return vandermonde_arnoldi_eval_der(X, self._R, self._indices, self.mode, weight = weight, V = self.Q)
+			return vandermonde_arnoldi_eval_der(X, self._R, self._indices, self.mode, weight = weight, V = self._Q)
 		else:
 			return vandermonde_arnoldi_eval_der(X, self._R, self._indices, self.mode, weight = weight)
 
diff --git a/polyrat/version.py b/polyrat/version.py
index 831fd7f..b7b6da0 100644
--- a/polyrat/version.py
+++ b/polyrat/version.py
@@ -1,2 +1,2 @@
-__version__ = '0.1.2'
+__version__ = '0.1.3'
 
diff --git a/tests/test_arnoldi.py b/tests/test_arnoldi.py
index d77c234..bc2d580 100644
--- a/tests/test_arnoldi.py
+++ b/tests/test_arnoldi.py
@@ -33,5 +33,23 @@ def wilkinson(x):
 	print("error", err)	
 	assert err < 1e-7, "Error too large"
 
+
+def test_arnoldi_vandermonde():
+	dim = 2
+	degree = 3
+	X = np.random.randn(100, dim)
+	arn = ArnoldiPolynomialBasis(X, degree)
+	
+	err = arn.basis() - arn.vandermonde(X)
+	norm_err = np.linalg.norm(err, 'fro')
+	assert norm_err < 1e-10
+	
+	# Note, these are already verified in test_basis -> test_vandermonde_derivative
+	# so the following checks are simply that the pass through access works correctly 
+	arn.vandermonde_derivative(X)
+	arn.vandermonde_derivative(np.random.randn(10, dim))
+
+
+
 if __name__ == '__main__':
 	test_arnoldi_roots(20)