diff --git a/R/constructors-Node.R b/R/constructors-Node.R
index 743dbb6..9b7a147 100644
--- a/R/constructors-Node.R
+++ b/R/constructors-Node.R
@@ -71,8 +71,8 @@ setMethod("NodeIdList", "character", function(object, uniquifyIds = c(TRUE, FALS
 
 #' @export 
 setMethod("NodeIdList", "data.frame", function(object, uniquifyIds = c(TRUE, FALSE)) {  
-  if (!isValidEdgeList(object)) {
-    stop(paste(errors, collapse = '\n'))
+  if (!inherits(isValidEdgeList(object), "logical")) {
+    stop(paste("Invalid edgeList:", isValidEdgeList(object), collapse = '\n'))
   }
 
   return(NodeIdList(c(object$source, object$target), uniquifyIds = uniquifyIds))
diff --git a/tests/testthat/test-nodes.R b/tests/testthat/test-nodes.R
index 122a5de..5e4034c 100644
--- a/tests/testthat/test-nodes.R
+++ b/tests/testthat/test-nodes.R
@@ -84,7 +84,6 @@ test_that("NodeList methods work", {
 test_that("We cannot make nonsensical nodes", {
 
   expect_error(Node(id = FALSE))
-  #expect_error(Node(id = 10)) # why is this nonsensical?
   expect_error(Node(id = 'A', color = FALSE))
   expect_error(Node(id = 'A', weight = '10'))
 })