As ever with butterfly spotting the likelihood of finding a good diversity and number on the wing depends on the weather on the day, and the weather in preceeding weeks, months and years. There is plenty of protected wide open flower filled space on The Lizard, so given the right conditions numbers of some species should be good.
The most likely to be encountered are:
Green Veined White
Silver Studded Blue
Small Pearl-Bordered Fritillary
Dark Green Fritillary
Details of butterfly species to be found and latest sightings can be found on the website of the Cornwall Branch of Butterfly Conservation.