diff --git a/biomes.lisp b/biomes.lisp
index 2382252..293d199 100644
--- a/biomes.lisp
+++ b/biomes.lisp
@@ -38,13 +38,13 @@
 	:name "grassland"
 	:ground "tall elephant grass"
 	:char #\; :col ':yellow
-	:features '((acacia 20) (boulder 100))) ;TODO
+	:features '((acacia 40) (boulder 150))) ;TODO
 
 (new-biome 'forest
 	:name "forest"
 	:ground "leaf litter and small shrubs"
 	:char #\. :col ':green
-	:features '((miombo 5) (acacia 10))) ;TODO
+	:features '((miombo 10) (acacia 15))) ;TODO
 
 (new-biome 'stream
 	:name "stream"
@@ -62,6 +62,6 @@
 	:name "hill"
 	:ground "hard, stony soil"
 	:char #\m :col ':white
-	:features '((boulder 7))) ;TODO
+	:features '((boulder 10))) ;TODO
 
 ;;TODO desert

diff --git a/biomes.lisp b/biomes.lisp
index 2382252..293d199 100644
--- a/biomes.lisp
+++ b/biomes.lisp
@@ -38,13 +38,13 @@
 	:name "grassland"
 	:ground "tall elephant grass"
 	:char #\; :col ':yellow
-	:features '((acacia 20) (boulder 100))) ;TODO
+	:features '((acacia 40) (boulder 150))) ;TODO
 
 (new-biome 'forest
 	:name "forest"
 	:ground "leaf litter and small shrubs"
 	:char #\. :col ':green
-	:features '((miombo 5) (acacia 10))) ;TODO
+	:features '((miombo 10) (acacia 15))) ;TODO
 
 (new-biome 'stream
 	:name "stream"
@@ -62,6 +62,6 @@
 	:name "hill"
 	:ground "hard, stony soil"
 	:char #\m :col ':white
-	:features '((boulder 7))) ;TODO
+	:features '((boulder 10))) ;TODO
 
 ;;TODO desert
diff --git a/naledi.lisp b/naledi.lisp
index c4cb5ba..54ad9ea 100644
--- a/naledi.lisp
+++ b/naledi.lisp
@@ -79,7 +79,7 @@
 							(progn (setf (.color-pair win) '(:white :black))
 								(add-char win #\X))
 							(if (patch-occupant p)
-								(progn ;FIXME throws an error
+								(progn
 									(setf (.color-pair win)
 										(list (.color (patch-occupant p))
 											:black))

diff --git a/biomes.lisp b/biomes.lisp
index 2382252..293d199 100644
--- a/biomes.lisp
+++ b/biomes.lisp
@@ -38,13 +38,13 @@
 	:name "grassland"
 	:ground "tall elephant grass"
 	:char #\; :col ':yellow
-	:features '((acacia 20) (boulder 100))) ;TODO
+	:features '((acacia 40) (boulder 150))) ;TODO
 
 (new-biome 'forest
 	:name "forest"
 	:ground "leaf litter and small shrubs"
 	:char #\. :col ':green
-	:features '((miombo 5) (acacia 10))) ;TODO
+	:features '((miombo 10) (acacia 15))) ;TODO
 
 (new-biome 'stream
 	:name "stream"
@@ -62,6 +62,6 @@
 	:name "hill"
 	:ground "hard, stony soil"
 	:char #\m :col ':white
-	:features '((boulder 7))) ;TODO
+	:features '((boulder 10))) ;TODO
 
 ;;TODO desert
diff --git a/naledi.lisp b/naledi.lisp
index c4cb5ba..54ad9ea 100644
--- a/naledi.lisp
+++ b/naledi.lisp
@@ -79,7 +79,7 @@
 							(progn (setf (.color-pair win) '(:white :black))
 								(add-char win #\X))
 							(if (patch-occupant p)
-								(progn ;FIXME throws an error
+								(progn
 									(setf (.color-pair win)
 										(list (.color (patch-occupant p))
 											:black))
diff --git a/world.lisp b/world.lisp
index ad888c7..087cf5b 100644
--- a/world.lisp
+++ b/world.lisp
@@ -128,7 +128,7 @@
 	(let ((flist (biome-features (patch-biome patch))))
 		(dolist (f flist NIL)
 			(when (chancep (second f))
-				(return-from get-patch-feature (first f))))))
+				(return-from get-patch-feature (get-item-type (first f)))))))
 
 (defun generate-biomes (size-factor world)
 	;;XXX The maps this produces don't look quite as expected, but for
@@ -161,7 +161,8 @@
 			  (if (probabilityp 75) dir (next-dir dir (random-elt '(T NIL)))))
 			 (patch (coord x0 y0 world) (neighbour patch dir world)))
 		((or (null patch) (eq (patch-biome patch) (get-biome 'stream))))
-		(setf (patch-biome patch) (get-biome 'stream))))
+		(setf (patch-biome patch) (get-biome 'stream))
+		(setf (patch-occupant patch) NIL)))
 
 ;;TODO create animal herds