diff --git a/main.js b/main.js
index eedf7a9..e2ddddc 100644
--- a/main.js
+++ b/main.js
@@ -121,8 +121,12 @@ function changeShape() {
 
 function setVisibility(option_name) {
 	const option = structure.options.filter((o) => o.name === option_name);
-	node_show = option[0].nodes;
-	link_show = option[0].links;
+	if( option.length ) {
+		node_show = option[0].nodes;
+		link_show = option[0].links;
+	} else {
+		console.log(`Error: option '${option_name}' not found`);
+	}
 }
 
 
diff --git a/polytopes.js b/polytopes.js
index f2a4d4e..fdc25c3 100644
--- a/polytopes.js
+++ b/polytopes.js
@@ -392,6 +392,8 @@ function link_labels(nodes, link) {
 }
 
 
+// version of the 120-cell where nodes are partitioned by 
+// layer and the links follow that
 
 export const cell120_layered = (max) => {
 	const nodes  = make_120cell_vertices();
@@ -399,6 +401,27 @@ export const cell120_layered = (max) => {
 
 	layered_120cell(nodes);
 
+	links.map((l) => {
+		const labels = link_labels(nodes, l);
+		if( labels[0] >= labels[1] ) {
+			l.label = labels[0];
+		} else {
+			l.label = labels[1];
+		}
+	});
+
+	const options = [];
+	const layers = [];
+
+	for( const i of [ 0, 1, 2, 3, 4, 5, 6 ] ) {
+		layers.push(i);
+		options.push({
+			name: "Layer " + String(i),
+			links: [...layers],
+			nodes: [...layers]
+		})
+	}
+
 	return {
 		name: '120-cell layered',
 		nodes: nodes,
@@ -407,8 +430,7 @@ export const cell120_layered = (max) => {
 			node_size: 0.02,
 			link_size: 0.02
 		},
-		options: [
-		]
+		options: options
 	}
 }
 
@@ -720,6 +742,7 @@ export const build_all = () => {
 		tesseract(),
 		cell24(),
 		cell600(),
-	 	cell120_inscribed()
+	 	cell120_inscribed(),
+	 	cell120_layered()
 	 	];
 }
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