The Need for Ichthyological Surveys of the Major Rivers of Western North America.

Exploration for " Big Bones " at Lower Blue Licks Spring, Kentucky: Willard Rouse Jillson 555 The Immunizing Effect in the Action of TrypanocidalAgents: Clifford S. Leonard .................................... 556 Thiophene-free Benzene: B.J.Graul and J. V. Karabinos .................................... 557 Pyridylmereuric Acetate as a Prophylactic in Fisheries Management: Willis M. Van Horn and Max Katz ............................ 557 A View on Soviet Russia From Italy: Samuel Levy 557