diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -38,4 +38,8 @@
 
 ## 0.6.1.0 -- 2024-01-23
 
-* Add checkFiniteSketch to be more specific.
+* Add checkFiniteSketch to be more specific.
+
+## 0.6.1.1 -- 2024-01-23
+
+* Bug fix in sketchMorphism
diff --git a/FiniteCategories.cabal b/FiniteCategories.cabal
--- a/FiniteCategories.cabal
+++ b/FiniteCategories.cabal
@@ -14,7 +14,7 @@
 -- PVP summary:      +-+------- breaking API changes
 --                   | | +----- non-breaking API additions
 --                   | | | +--- code changes with no API change
-version:             0.6.1.0
+version:             0.6.1.1
 
 -- A short (one-line) description of the package.
 synopsis: Finite categories and usual categorical constructions on them.
diff --git a/src/Math/Categories/FinSketch.hs b/src/Math/Categories/FinSketch.hs
--- a/src/Math/Categories/FinSketch.hs
+++ b/src/Math/Categories/FinSketch.hs
@@ -267,7 +267,7 @@
             errFunct = checkDiagram f
             fromJust (Just x) = x
             faultyCone = find (\cone_ -> not $ (unsafeCone (f ->$ (apex cone_)) (f <-@<= legsCone cone_)) `Set.isIn` (distinguishedCones t)) (distinguishedCones s)
-            faultyCocone = find (\cocone_ -> not $ (unsafeCocone (f ->$ (nadir cocone_)) (legsCocone cocone_ <=@<- f)) `Set.isIn` (distinguishedCocones t)) (distinguishedCocones s)
+            faultyCocone = find (\cocone_ -> not $ (unsafeCocone (f ->$ (nadir cocone_)) (f <-@<= legsCocone cocone_)) `Set.isIn` (distinguishedCocones t)) (distinguishedCocones s)
             faultyTripod = find (\tripod_ -> not $ (unsafeTripod (unsafeCone (f ->$ (apex (twoCone tripod_))) (f <-@<= legsCone (twoCone tripod_))) (f ->£ (evalMap tripod_))) `Set.isIn` (distinguishedTripods t)) (distinguishedTripods s)
             
 
@@ -276,7 +276,7 @@
     canFunctorBePromotedIntoSketchMorphism s t f = null faultyCone && null faultyCocone && null faultyTripod
         where
             faultyCone = find (\cone_ -> not $ (unsafeCone (f ->$ (apex cone_)) (f <-@<= legsCone cone_)) `Set.isIn` (distinguishedCones t)) (distinguishedCones s)
-            faultyCocone = find (\cocone_ -> not $ (unsafeCocone (f ->$ (nadir cocone_)) (legsCocone cocone_ <=@<- f)) `Set.isIn` (distinguishedCocones t)) (distinguishedCocones s)
+            faultyCocone = find (\cocone_ -> not $ (unsafeCocone (f ->$ (nadir cocone_)) (f <-@<= legsCocone cocone_)) `Set.isIn` (distinguishedCocones t)) (distinguishedCocones s)
             faultyTripod = find (\tripod_ -> not $ (unsafeTripod (unsafeCone (f ->$ (apex (twoCone tripod_))) (f <-@<= legsCone (twoCone tripod_))) (f ->£ (evalMap tripod_))) `Set.isIn` (distinguishedTripods t)) (distinguishedTripods s)