Pterodactyloidea Pterodactyloidea Pterodactyloidea (derived from the Greek words "πτερόν" ("pterón", for usual "ptéryx") "wing", and "δάκτυλος" ("dáctylos") "finger" meaning "winged finger", "wing-finger" or "finger-wing") is one of the two traditional suborders of pterosaurs ("wing lizards"), and contains the most derived members of this group of flying reptiles. They appeared during the middle Jurassic Period, and differ from the basal (though paraphyletic) rhamphorhynchoids by their short tails and long wing metacarpals (hand bones). The most advanced forms also lack teeth, and by the late Cretaceous, all known pterodactyloids were toothless. Many species had well developed crests on the skull, a form of
Helen (given name) Jerusalem. Helen enjoyed a massive burst of popularity in the United States during the first half of the 20th century, when it was one of the top ten names for baby girls, but became less common following World War 2. The name "Eilidh" (pronounced "ayley") is a Gaelic version of the name Helen. Helen (given name) Helen is a feminine given name derived from the Ancient Greek name , "Helenē" (dialectal variant: , "Helena") whose etymology is unknown; a derivation of the latter from , a variant form of , i.e. "torch", is considered "rather uncertain". Another possible derivation is