Fig. 8
From: NANUQ: a method for inferring species networks from gene trees under the coalescent model

An m-dart, for \(m=5,6,7\) respectively. The frontier edges, shown in bold outline, are characterized in the text. The outer vertices labelled by the \(X_i\) are the corners. The point of the dart is the unique corner which is \(m-3\) frontier edges away from the closest corners