Ooh, I LOVE Evadne (assuming your title is a typo?) but have never seen or heard it used except in the Chalet School books! Great name.
Gwendoline, Evadne, Julian and ...
Anika, Arrietty, Anoushka, Ariana, Alyona, Amberley, Annalise, Araminta, Atlanta
Bryony, Belinda, Brielle, Bronwen, Bridget
Calliope, Cordelia, Cressida, Camilla, Clarice, Carlotta, Carmen, Carys, Celest
Daphne, Demelza, Danica, Delilah, Delia, Delphi
Emmeline, Eloise, Eliana, Elora, Elara
Fenella, Francesca, Felicity, Fabia, Faith
Gabriella, Genevieve, Gloria
Hermione, Harmony, Harper, Hallie, Hazel
Isadora, Imelda, Iris
Jessamy, Jacinta, Jonquil, Josette, Josephine, Jerica, Joanna
Kerensa, Kirsten, Katrina, Katinka, Keziah
Lorelai, Larissa, Leonie, Liliana, Lydia, Liara, Luana, Livia
Miranda, Melinda, Marissa, Miriam, Marnie, Mika, Marianne, Meredith, Mirabelle
Natasha, Neriah, Noelle, Nadia, Natalia
Ondine, Odette, Octavia, Ophelia
Philippa, Piper, Persephone, Primrose, Pandora, Paloma
Quinn
Ramona, Romilly, Rivkah, Rowena, Rosina, Rosanna, Rosita, Rowan, Robyn
Sadie, Saskia, Sabrina, Sorrel, Saffron, Susannah, Stephanie, Seren, Sylvia
Taryn, Tegan, Talitha, Tamara, Tamsin, Tasmin, Thea, Tallulah, Tamika
Verity, Vivianne, Vanessa, Vashti
Xanthe
Zipporah, Zeryn, Zara, Zia