Fig. 3From: The Origin of the Vertebrate EyeSouthern hemisphere lamprey, Geotria australis. a Larval form, “ammocoete”. b Post-metamorphic, “downstream” adult form. Note that the ammocoete has the mouth and seven gill slits but that there is no sign of an eye at the surface. Instead, there is a rudimentary and small eye-like organ buried deep beneath the skin. In this and several other regards, the ammocoete resembles the hagfish. Photographs courtesy of G. Westhoff and S.P. CollinBack to article page