TreeView is a simple program for displaying phylogenies. Some of its
features include:

- reads many different tree file formats (including NEXUS, PHYLIP, 
  Hennig86, NONA, MEGA, and ClustalW/X)
- supports standard the TrueType and Postscript fonts
- supports native graphics file format for copying pictures into 
  other applications, and for saving graphics files
- print preview
- can print multiple trees per page and/or one tree over more than 
  one page
- has drag-and-drop facility for easy opening of files
- Web-based online help
- tree editor

For details and citation:
Page, R. D. M. 1996. TREEVIEW: An application to display phylogenetic 
trees on personal computers. Computer Applications in the Biosciences 
12: 357-358. 

This requires wxGTK or wxPython, available at SlackBuilds.org.