diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # recursion
 
+## 2.0.0.0
+
+* Add `zygoM'`, the second monadic zygomorphism
+* Remove `scolio`, `dendro`, and `chema`
+
 ## 1.2.2.0
 
 * Add `zygoM`
diff --git a/recursion.cabal b/recursion.cabal
--- a/recursion.cabal
+++ b/recursion.cabal
@@ -1,6 +1,6 @@
 cabal-version:      1.18
 name:               recursion
-version:            1.2.2.0
+version:            2.0.0.0
 license:            BSD3
 license-file:       LICENSE
 copyright:          Copyright: (c) 2018 Vanessa McHale
@@ -32,7 +32,7 @@
     default-language: Haskell2010
     other-extensions:
         DeriveFunctor FlexibleContexts ExistentialQuantification RankNTypes
-        TypeFamilies
+        TypeFamilies DeriveFoldable DeriveTraversable
     ghc-options:      -Wall
     build-depends:
         base >=4.9 && <5,
diff --git a/src/Control/Recursion.hs b/src/Control/Recursion.hs
--- a/src/Control/Recursion.hs
+++ b/src/Control/Recursion.hs
@@ -1,4 +1,6 @@
+{-# LANGUAGE DeriveFoldable            #-}
 {-# LANGUAGE DeriveFunctor             #-}
+{-# LANGUAGE DeriveTraversable         #-}
 {-# LANGUAGE ExistentialQuantification #-}
 {-# LANGUAGE FlexibleContexts          #-}
 {-# LANGUAGE RankNTypes                #-}
@@ -36,13 +38,10 @@
     , mcata
     -- * Monadic recursion schemes
     , cataM
-    , zygoM
     , anaM
     , hyloM
-    -- * Mutual recursion
-    , scolio
-    , dendro
-    , chema
+    , zygoM
+    , zygoM'
     -- * Helper functions
     , lambek
     , colambek
@@ -80,10 +79,10 @@
 
 data ListF a b = Cons a b
                | Nil
-               deriving (Functor)
+               deriving (Functor, Foldable, Traversable)
 
 data NonEmptyF a b = NonEmptyF a (Maybe b)
-    deriving (Functor)
+    deriving (Functor, Foldable, Traversable)
 
 newtype Fix f = Fix { unFix :: f (Fix f) }
 
@@ -178,10 +177,12 @@
 cataM :: (Recursive t, Traversable (Base t), Monad m) => (Base t a -> m a) -> t -> m a
 cataM f = c where c = f <=< (traverse c . project)
 
---  (Base t b -> b) -> (Base t (b, a) -> a) -> t -> a
 zygoM :: (Recursive t, Traversable (Base t), Monad m) => (Base t b -> m b) -> (Base t (b, a) -> m a) -> t -> m a
 zygoM f g = fmap snd . cataM (\x -> (,) <$> f (fmap fst x) <*> g x)
 
+zygoM' :: (Recursive t, Traversable (Base t), Monad m) => (Base t b -> m b) -> (Base t (b, a) -> m a) -> t -> m a
+zygoM' f g = fmap snd . cataM (\x -> do { a <- g x; b <- f (fmap fst x); pure (b, a) })
+
 anaM :: (Corecursive t, Traversable (Base t), Monad m) => (a -> m (Base t a)) -> a -> m t
 anaM f = a where a = (fmap embed . traverse a) <=< f
 
@@ -278,32 +279,3 @@
 
 refix :: (Recursive s, Corecursive t, Base s ~ Base t) => s -> t
 refix = cata embed
-
--- | Entangle two hylomorphisms.
-scolio :: (Functor g)
-    => ((f b -> b) -> Trans b b) -- ^ A pseudoprism parametric in an \\( F \\)-algebra that allows @b@ to inspect itself.
-    -> ((a -> f a) -> Lens a a) -- ^ A lens parametric in an \\( F \\)-coalgebra that allows @b@ to inspect itself.
-    -> (g b -> b) -- ^ A @g@-algebra
-    -> (a -> g a) -- ^ A @g@-coalgebra
-    -> (f b -> b) -- ^ An @f@-algebra
-    -> (a -> f a) -- ^ An @f@-coalgebra
-    -> a -> b
-scolio p l alg coalg alg' coalg' = hylo (p alg' alg) (l coalg' coalg)
--- TODO: figure out rewrite rules
--- also a more flexible approach would be good.
-
--- Entangle two anamorphisms.
-chema :: (Corecursive t')
-    => ((a -> f a) -> Lens b b) -- ^ A lens parametric in an \\( F \\)-coalgebra that allows @b@ to inspect itself.
-    -> (a -> f a) -- ^ A @(Base t)@-coalgebra
-    -> (b -> Base t' b) -- ^ A @(Base t')@-coalgebra
-    -> b -> t'
-chema = (ana .*)
-
--- | A dendromorphism entangles two catamorphisms
-dendro :: (Recursive t')
-    => ((f a -> a) -> Trans b b) -- ^ A pseudoprism parametric in an \\(F \\)-algebra that allows @b@ to inspect itself.
-    -> (f a -> a) -- ^ A @(Base t)@-algebra
-    -> (Base t' b -> b) -- ^ A @(Base t')@-algebra
-    -> t' -> b
-dendro = (cata .*)