Scintillating Scotoma. (Migraine Scotoma). A scotoma is a âblind spotâ in front of the vision. The visual phenomenon of scintillating scotoma usually appears like a âtwinkling shadowâ or âzig zag patternâ before the eyes.While every experience is a little different, the most common symptoms are âblack spotâ or âtwinkling blurâ appearing before the eyes.he visual phenomenon of scintillating scotoma usually appears like a âtwinkling shadowâ or âzig zag patternâ before the eyes. While every experience is a little different, the most common symptoms are âblack spotâ or âtwinkling blurâ appearing before the eyes.
Cancel. Spiders live all over the world, including trees, dry areas, wet areas, under ground and in the oceans. Discover the different varieties of spiders on the earth with information from a science teacher in this free video on spider habitats.ancel. Spiders live all over the world, including trees, dry areas, wet areas, under ground and in the oceans. Discover the different varieties of spiders on the earth with information from a science teacher in this free video on spider habitats.
Hunting spiders rely on their eyesight and speed to catch their prey while web-building spiders spin a strong silk into a web to catch their prey. In the mid-west, there are six main types of hunting spiders and three types of web-building spiders. Learn about hunting spiders native to the mid-west.The six hunting spiders native to the mid-west are jumping spiders, wolf spiders, fishing spiders, sac spiders, crab spiders and parson spiders. Sac spiders, wolf spiders and jumping spiders can be found but indoors and outdoors.