An Orthodenticle

A <a href="https://en.m.wiktionary.org/wiki/homeobox" title="homeobox" style="margin: 0px; padding: 0px; border: 0px; font-variant-numeric: inherit; font-variant-east-asian: inherit; font-stretch: inherit; line-height: inherit; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Lato, Helvetica, Arial, sans-serif; vertical-align: baseline; background: none rgb(255, 255, 255); color: rgb(107, 75, 161); hyphens: none;">homeobox</a> <a href="https://en.m.wiktionary.org/wiki/gene" title="gene" style="margin: 0px; padding: 0px; border: 0px; font-variant-numeric: inherit; font-variant-east-asian: inherit; font-stretch: inherit; line-height: inherit; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Lato, Helvetica, Arial, sans-serif; vertical-align: baseline; background: none rgb(255, 255, 255); color: rgb(107, 75, 161); hyphens: none;">gene</a> involved in the <a href="https://en.m.wiktionary.org/wiki/development" title="development" style="margin: 0px; padding: 0px; border: 0px; font-variant-numeric: inherit; font-variant-east-asian: inherit; font-stretch: inherit; line-height: inherit; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Lato, Helvetica, Arial, sans-serif; vertical-align: baseline; background: none rgb(255, 255, 255); color: rgb(107, 75, 161); hyphens: none;">development</a> of the <a href="https://en.m.wiktionary.org/wiki/head" title="head" style="margin: 0px; padding: 0px; border: 0px; font-variant-numeric: inherit; font-variant-east-asian: inherit; font-stretch: inherit; line-height: inherit; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Lato, Helvetica, Arial, sans-serif; vertical-align: baseline; background: none rgb(255, 255, 255); color: rgb(107, 75, 161); hyphens: none;">head</a>.