diff --git a/core/modules/filters/eachday.js b/core/modules/filters/eachday.js
index 9a91bc30b..350830564 100644
--- a/core/modules/filters/eachday.js
+++ b/core/modules/filters/eachday.js
@@ -17,15 +17,16 @@ Export our filter function
 */
 exports.eachday = function(source,operator,options) {
 	var results = [],
-		values = [];
+		values = [],
+		fieldName = operator.operand || "modified";
 	// Function to convert a date/time to a date integer
 	var toDate = function(value) {
 		value = (new Date(value)).setHours(0,0,0,0);
 		return value+0;
 	};
 	source(function(tiddler,title) {
-		if(tiddler && tiddler.fields[operator.operand]) {
-			var value = toDate(tiddler.fields[operator.operand]);
+		if(tiddler && tiddler.fields[fieldName]) {
+			var value = toDate(tiddler.fields[fieldName]);
 			if(values.indexOf(value) === -1) {
 				values.push(value);
 				results.push(title);
diff --git a/editions/tw5.com/tiddlers/filters/eachday.tid b/editions/tw5.com/tiddlers/filters/eachday.tid
index b965ff96e..a91857f55 100644
--- a/editions/tw5.com/tiddlers/filters/eachday.tid
+++ b/editions/tw5.com/tiddlers/filters/eachday.tid
@@ -1,12 +1,12 @@
 created: 20140410103123179
-modified: 20150203184456000
+modified: 20150210161620000
 tags: [[Filter Operators]] [[Group Operators]] [[Date Operators]]
 title: eachday Operator
 type: text/vnd.tiddlywiki
 caption: eachday
 op-purpose: select one of each group of input titles by date
 op-input: a [[selection of titles|Title Selection]]
-op-parameter: the name of a [[date field|Date Fields]]
+op-parameter: the name of a [[date field|Date Fields]], defaulting to <<.field modified>>
 op-parameter-name: F
 op-output: a selection containing the first input title encountered for each distinct value (ignoring times of day) of field <<.place F>>