http://library.thinkquest.org/27968/from_egg_to_butterfly.shtml

http://library.thinkquest.org/C002251/cgi-bin/default.cgi?language=english&mode=chapter&outputmode=0&navmenu=1&javascript=1&chapter=0&section=4

http://www.mesc.usgs.gov/resources/education/butterfly/life%2Dcycle/butterfly%2Dlife%2Dcycle.asp

http://www.npwrc.usgs.gov/resource/distr/lepid/bflyusa/bflyusa.htm