diff --git a/src/hdnode.js b/src/hdnode.js
index 627b67d..0b2399c 100644
--- a/src/hdnode.js
+++ b/src/hdnode.js
@@ -51,7 +51,7 @@ HDNode.HIGHEST_BIT = 0x80000000
 HDNode.LENGTH = 78
 
 HDNode.fromSeedBuffer = function(seed, network) {
-  assert(Buffer.isBuffer(seed), 'Expected Buffer, got' + seed)
+  assert(Buffer.isBuffer(seed), 'Expected Buffer, got ' + seed)
   assert(seed.length >= 16, 'Seed should be at least 128 bits')
   assert(seed.length <= 64, 'Seed should be at most 512 bits')