diff --git a/app/assets/javascripts/darkswarm/filters/taxons.js.coffee b/app/assets/javascripts/darkswarm/filters/taxons.js.coffee
index 3eb32ce1a4..a7ccc9b0cc 100644
--- a/app/assets/javascripts/darkswarm/filters/taxons.js.coffee
+++ b/app/assets/javascripts/darkswarm/filters/taxons.js.coffee
@@ -1,13 +1,16 @@
-Darkswarm.filter 'taxons', (Matcher)-> 
-  # Filter anything that responds to object.taxons, and/or object.primary_taxon
+Darkswarm.filter 'taxons', ()->
+  # Filter anything that responds to object.taxons, object.supplied_taxon or object.primary_taxon.
   (objects, ids) ->
     objects ||= []
     ids ?= []
     if ids.length == 0
+      # No taxons selected, pass all objects through.
       objects
     else
       objects.filter (obj)->
         taxons = obj.taxons
-        taxons.concat obj.supplied_taxons if obj.supplied_taxons
+        # Combine object taxons with supplied taxons, if they exist.
+        taxons = taxons.concat obj.supplied_taxons if obj.supplied_taxons
+        # Match primary taxon if it exists, then taxon array.
         obj.primary_taxon?.id in ids || taxons.some (taxon)->
           taxon.id in ids