diff --git a/classdesc b/classdesc
index 2ead63b..7701bf3 160000
--- a/classdesc
+++ b/classdesc
@@ -1 +1 @@
-Subproject commit 2ead63b60bf4f564ca08c290f8ab221d2eda09cf
+Subproject commit 7701bf30bb818af2ef262ce060148e14d7eb641b
diff --git a/lib/plot.py b/lib/plot.py
index bf65aea..576a9b3 100644
--- a/lib/plot.py
+++ b/lib/plot.py
@@ -7,7 +7,7 @@
 def getPlot(name):
     plotName='plot#'+name.replace(' ','')
     if not plotName in ecolab.__dict__:
-        Plot(plotName)
+        ecolab.register(Plot(),plotName)
         plotWindow=Tk()
         plotWindow.wm_title(name)
         plotWindow.eval('load '+ecolabHome()+'/lib/ecolab.so')
diff --git a/models/panmictic_ecolab.py b/models/panmictic_ecolab.py
index 2cb9597..9810193 100644
--- a/models/panmictic_ecolab.py
+++ b/models/panmictic_ecolab.py
@@ -48,7 +48,7 @@ def step():
     nsp=len(ecolab.species)
     statusBar.configure(text=f't={ecolab.tstep()} nsp:{nsp}')
     plot('No. species',ecolab.tstep(),nsp)
-    plot('Density',ecolab.tstep(),ecolab.density()._properties, pens=ecolab.species()._properties)
+    plot('Density',ecolab.tstep(),ecolab.density(), pens=ecolab.species())
     
 gui(step)