when laid forward barely or not reaching eye; tail shorter than (rarely equal to) the length of head and body, darker above than below; color of body normally grey-brown above, white below; hind foot 38–46 millimeters" (Lantz). The common albino rat (Miis norvegicus albinus) is a variety of the Norway rat, and is now known only as a domesticated animal. Mus rattus also has been known to produce albinos. The large number of wild Norway rats that can usually be caught in human communities, together with the ease with which albinos can now be secured from dealers, makes the Norway rat a convenient form for laboratory study by large classes. Either the wild Norway rat or its albino variety can be used for dissection in connection with the directions and descriptions contained in this manual.
