Tree Porcupine
http://www.ehow.com/about_6635031_tree-porcupine.html
http://www.thekidsworld.net/1/tree_porcupine.htm
http://animals.nationalgeographic.com/animals/mammals/porcupine.html
http://www.hww.ca/hww2.asp?id=100
http://en.wikipedia.org/wiki/Porcupine