Dear R-help list, I'd like to create visualize the clustering of a dataset with a dendrogram. I'm using the following script: data = read.table("data.csv", header=T, sep=";") require(cluster) res = as.dendrogram(agnes(data)) chlab <- function(n) { if(is.leaf(n)) { att <- attributes(n) labx <- data$category1[att$label] lab_color <- ifelse(labx == "A", "black", ifelse(labx == "B", "red", "green")) attr(n, "nodePar") <- c(att$nodePar, lab.col = lab_color, pch = NA) attr(n, "label") <- labx } n } # lab.col = lab_color, res2 = dendrapply(res, chlab) print(res2) pdf("dendrogram.pdf",width=5,height=2.5,pointsize=8,paper='special') par(mai=c(0.5,0.5,0.2,0.2)) plot(res2) dev.off() This works nicely with the exception of one detail: the labels are perpendicular to the normal reading direction. I'm aware of the leaflab="textlike" option which does put the labels horizontally, however, it also draws rectangles around the labels which I don't want. How can I create a dendrogram with horizontal labels, without those rectangles? Some example data for the script: code;name;sex;date1;exp_type;exp1;category1;comment1;sar1;distance1;order1;n_trials;run1_name_cond1_rt;run1_name_cond2_rt;run1_name_cond3_rt;run1_name_cond1_er;run1_name_cond2_er;run1_name_cond3_er;run1_col_cond1_rt;run1_col_cond2_rt;run1_col_cond4_rt;run1_col_cond1_er;run1_col_cond2_er;run1_col_cond4_er;run2_name_cond1_rt;run2_name_cond2_rt;run2_name_cond3_rt;run2_name_cond1_er;run2_name_cond2_er;run2_name_cond3_er;run2_col_cond1_rt;run2_col_cond2_rt;run2_col_cond4_rt;run2_col_cond1_er;run2_col_cond2_er;run2_col_cond4_er 00;xxx;F;Tue Sep 6 12:53:19 2011;umts;0;C;;1.80;5.0;0;20;1009.35;1394.65;1046.95;0;0.05;0;1222.25;1136.75;1012.65;0;0;0;884.7;1004.8;1003.45;0;0;0;813.3;1045.75;946;0;0;0 01;xxx;N;Tue Sep 6 14:51:18 2011;umts;1;B;;1.80;5.0;1;20;1042.15;1073.6;1087.7;0;0;0;1501.45;1932.6;1210.8;0;0.2;0;805.9;776.35;800.35;0;0;0;937.65;1094.1;917.6;0;0.05;0 02;xxx;F;Wed Sep 7 10:49:16 2011;lte;1;A;;1.80;5.0;0;20;1084.05;912;769.45;0.05;0.1;0;785.2;1137;925.6;0;0.1;0;955.1;1013.45;955;0;0.05;0.05;917.6;1383.4;876.45;0;0.1;0 03;xxx;F;Wed Sep 7 15:00:56 2011;lte;0;C;;1.80;5.0;1;20;1226.65;1329.6;1218.95;0;0;0;1371.9;2126.25;1356.05;0;0.1;0;1065.25;1379.15;1091.75;0.05;0.05;0;1370.7;2654.75;1314.55;0;0.15;0 04;xxx;F;Thu Sep 8 09:20:03 Thanks in advance for your answer: P?ter Juh?sz