Alosa "oligorakered." The multirakered are primarily plankton feeders, the oligorakered have large rakers and are predators, and the medium-rakered generally consume a mixed diet. Most current species of the genus "Alosa" in North America can be found in Florida, whereas the distribution of most of them is broader. Morphology is notoriously liable to adapt to changing food availability in these fish. Several taxa seem to have evolved quite recently, making molecular analyses difficult. In addition, hybridization may be a factor in shad phylogeny. Nonetheless, some trends are emerging. The North American species except the American shad "A. sapidissima" can probably be
Fox River (Fish River tributary) tributary of Fox River, known as Blue Rock Creek. I X L Gulch is a small tributary which heads about a mile southwest of Fox River. Slate Creek is another tributary, from the south. Along Fox River, about south of Council, there are several dikes of greenstone that under the microscope are found to be slightly altered diabase. They consist of labradorite and olivine phenocrysts in a groundmass of plagtoclase, augite, and biotite. Some greenstone masses which appeared to be slightly altered tuffs were found in the divide between Fox and Solomon rivers. Fox River (Fish River tributary) Fox River