What we have described as tentacles are fairly long, reddish, knobbed glandular hairs emerging from the upper surface of the leaves. Glimmering in the sunshine, the tiny drops of viscid fluid form an attraction to small insects. Hapless flies settling on the leaves in the hopes of securing a sweet morsel are speedily and fatally undeceived..

— A Pocket Book of British Wild Flowers by Charles A. Hall

Illustration by C. F. Newall [1937]