In the frist story, Cathouse, a lone civilian, Locklear, is stranded on a distant planet after a Kzinti attack, in what appears to be an alien zoo. His only companions are two female Kzin who, to his surprise, turn out to be sentient (a trait that's been bred out of modern Kzin females).
In the second story, Briar Patch, Locklear leaves the three Kzin Scarface, Kit and Boots to explore the earthlike habitat of the mysterious alien zoo, and discovers that the stasis cave on that side of the force shield is full of Neanderthals.
The stories take place on a planet called Cathouse or Zoo.
Republished in The Houses of the Kzinti (2002).
The Man-Kzin Wars (1988, Larry Niven, Poul Anderson, Dean Ing)
Man-Kzin Wars II (1989, Dean Ing, Jerry Pournelle and S.M. Stirling)
Man-Kzin Wars III (1990, Larry Niven, Poul Anderson, Jerry Pournelle and S.M. Stirling)
Man-Kzin Wars IV (1991, Donald Kingsbury, Greg Bear and S.M. Stirling)
Man-Kzin Wars V (1992, Thomas T. Thomas, Jerry Pournelle and S.M. Stirling)
Man-Kzin Wars VI (1994, Donald Kingsbury, Mark O. Martin and Gregory Benford)
Man-Kzin Wars VII (1995, Hal Colebatch, Paul Chafe, Mark O. Martin and Gregory Benford)
Man-Kzin Wars VIII: Choosing Names (1998, Larry Niven, Hal Colebatch, Jean Lamb, Paul Chafe and Warren W. James?)
The Best of All Possible Wars: The Best of the Man-Kzin Wars (1998)
Man-Kzin Wars IX (2002, Larry Niven, Poul Anderson, Hal Colebatch, Paul Chafe)
Man-Kzin Wars X: The Wunder War (2003, Hal Colebatch)
Man-Kzin Wars XI (2005, Larry Niven, Hal Colebatch and Matthew Joseph Harrington)
Man-Kzin Wars XII (2009, Paul Chafe, Hal Colebatch and Matthew Joseph Harrington)
Man-Kzin Wars XIII (2012, Hal Colebatch, Matthew Joseph Harrington, Paul Chafe, Jessica Q. Fox?, Jane Lindskold, Charles E. Gannon?, Alex Hernandez and David Bartell)
Cathouse: A Novel of the Man Kzin-Wars (1990 Dean Ing)
The Children's Hour: A Novel of the Man-Kzin Wars (1991, Jerry Pournelle and S. M. Stirling)
Inconstant Star (1991, Poul Anderson)
A Darker Geometry (1996, Mark O. Martin? and Gregory Benford)
The Houses of the Kzinti (2002, Dean Ing, Jerry Pournelle, S. M. Stirling)
Destiny's Forge: A Man-Kzin Wars Novel (2007, Paul Chafe)
Annals of the Man-Kzin-Wars: An Unofficial Companion Guide (Alan Michaud?, 2001)