diff --git a/convex-core/src/main/cvx/convex/torus/exchange.cvx b/convex-core/src/main/cvx/convex/torus/exchange.cvx
index 4071ee623..5729ee1c3 100644
--- a/convex-core/src/main/cvx/convex/torus/exchange.cvx
+++ b/convex-core/src/main/cvx/convex/torus/exchange.cvx
@@ -194,8 +194,7 @@
         (let [tok token-balance
               cvm *balance*] 
           (cond (and (> tok 0) (> cvm 0))
-            (/ cvm
-               tok))))
+            (/ cvm tok))))
 
 
       (defn sell-cvx
@@ -299,7 +298,9 @@
               own-holding  (or (get-holding *caller*) 0)
               
               ;; Check withrawal amount is valid
-              _            (or (<= 0 shares own-holding) (fail :FUNDS "Insufficient shares"))
+              _            (cond 
+            		         (> shares own-holding) (fail :FUNDS "Insufficient shares")
+            		         (< shares 0) (fail :ARGUMENT "Negative withdrawal"))
               
               proportion   (if (> supply
                                   0)
@@ -449,7 +450,7 @@
 
 
 (defn price
-  ^{:doc {:description "Gets the current price for a token, in CVX or an optional given currency. Returns nil if a market with liquidity does not exist."
+  ^{:doc {:description "Gets the current price for a token, in CVM or an optional given currency. Returns nil if a market with liquidity does not exist."
           :examples  [{:code "(price USD)"}
                       {:code "(price GBP USD)"}]
           :signature [{:params [token]}
@@ -507,7 +508,7 @@
              (sell-cvx-quote cvx-amount))))))
 
 (defn sell-tokens
-  ^{:doc {:description "Sell tokens at current CVX price"
+  ^{:doc {:description "Sell tokens at current CVM price"
           :signature   [{:params [token amount]}]}}
   [token amount]
   (let [market (or (get-market token)
diff --git a/convex-core/src/test/java/convex/actors/TorusTest.java b/convex-core/src/test/java/convex/actors/TorusTest.java
index 5bd9785d9..853c17f62 100644
--- a/convex-core/src/test/java/convex/actors/TorusTest.java
+++ b/convex-core/src/test/java/convex/actors/TorusTest.java
@@ -228,6 +228,7 @@ public class TorusTest extends ACVMTest {
 		assertEquals(RT.cvm(4.0),eval(ctx,"(torus/price TOK)"));
 		
 		assertFundsError(step(ctx,"(torus/withdraw-liquidity TOK 10001)"));
+		assertArgumentError(step(ctx,"(torus/withdraw-liquidity TOK -100)"));
 	}
 	
 	@Test public void testLiquidityZeroCVM() {
diff --git a/convex-core/src/test/java/convex/core/data/FuzzTestFormat.java b/convex-core/src/test/java/convex/core/data/FuzzTestFormat.java
index cb01c085b..871fbb069 100644
--- a/convex-core/src/test/java/convex/core/data/FuzzTestFormat.java
+++ b/convex-core/src/test/java/convex/core/data/FuzzTestFormat.java
@@ -68,7 +68,7 @@ public static void doCellFuzzTests(ACell c)  {
 	private static void doFuzzTest(Blob b) throws BadFormatException {
 		ACell v;
 		try {
-			v = Format.read(b);
+			v = Format.read(b,0);
 		} catch (ArrayIndexOutOfBoundsException e) {
 			System.out.println("Badd fuzzed read: "+b);
 			throw e;