Trophy specimens of most species own the night. While it's true they can detect prey by lateral-line-sensed vibrations, most remain primarily visual predators. Nature has provided them with eyes that change sensitivity to increase low-light visual acuity. So how does a fly fisher venturing out at night take advantage of this see-in-the-dark ability? Phosphorescent materials. Flies that glow in the dark have proven themselves from the trout lakes of New Zealand to the snook haunts of the Gulf of Mexico. Moreover, even in daylight, flies destined to fish in the gloom of the depths will benefit from an inherent glow. UNI Products, a world leader in supplying spooled materials for fly-tying, now offers the fly-tier a full line of phosphorescent materials to create a myriad of patterns. With the addition of Glo-Thread and Glo-Floss to the previously available UNI-Glo tinsel, no part of your fly needs to be dull. The photograph demonstrate the effect of these products. The Little Night Music, from David Phares of Arizona has proven very successful for snook in the Gulf of Mexico.