This butterfly is pattern #75 in the book “75 Lace Crochet Motifs.” Instructions on page 115. Featured on page 28 of the showcase.

Finished height: 2-3/8 inches (60 mm).
Thread required: 8 yards (7.3 m).

All pattern samples in this book are made with size 10 thread and a size 7 (1.65 mm) crochet hook.