I have read relatively recent articles that suggest that the Byblis plants do not produce enzymes. It appears that this is not the case, at least for Byblis filifolia: http://www.hartmeyer.de/homepageGB.htm. I plan to try a crude test on my Byblis gigantea as soon as I can find the time. I'm also convinced that this plant is a carnivore because I have observed juices dripping down the leaves after large catches. The plant appears to produce digestive jucies that are then re-absorbed in a similar way to Drosophyllum. I'm particularly glad to discover the true nature of Byblis filifolia as I currently have several seedlings of this species growing in my terrarium- I'll have to get feeding them!