wly fertilized egg is one point four millimeters in diameter. When the egg is in the stage of morula, it is one point four millimeters in diameter. The egg is one point five millimeters in diameter when it is at the early stage of being an embryo. During the late stages of being an embryo the egg is one point five millimeters in diameter. Most of the sculpins eggs are shaped spherically. The yolk is orange (Krejsa 1967), [On-line]; creamy yellow-white (Millikan 1968), [On-line]; yellowish, partially clear and partially granular. One large oil globule (between zero point two and zero point three millimeters in diameter), with many small oil globules congregating in yolk sac. The chorion is transparent, thick and hard. The Perivitelline space is between zero point one and zero point two millimeters in width. The eggs are very adhesiveto one another but less so to substrate. The buoyancy of the egg is demersal. Although newly hatched larvae are pelagic and are able to swim immediately (Krejsa 1967; Millikan 1968), [On-line]. The newly hatched prolarva may remain in the nest for a few hours until its body straightens out and it becomes free-swimming. Prickly sculpin for example do not have air bladders; they are usually bottom-dwellers. The very young like to swim just below the surface film so they can float along with the currents. In lakes, newly hatched sculpins swim up to the surface. It has been suggested that larval sculpin may use surface tension to maintain their position (Mason and Machidori 1976),[On-line]. Larvae remain planktonic and near the water surface for a period of 30-35 days (Krejsa 1967; Mason and Machidori 1976), [On-line]. According to Hershey (1985) “They are especially abundant at the surface during the darkest hours, moving into deeper water during the day. This allows them to feed off tiny plankton, which are most abundant near the surface” (p. 483). When the Larvae are newly hatched...
