Probably no group of fossil organisms except the Foraminifera has received more active study during the past decade than the Ostracoda, partly because of their scientific interest but mainly because of their importance in economic geology. The oil geologist finds the ostracods especially useful because their small size enables them to escape destruction by the drill, and the excellent preservation of the carapaces, with more or less distinctly marked surfaces, permits more certain specific identifications. Moreover, they are less subject to the influences of lithologic changes; the same fauna may persist in a formation whether it be limestone, shale, or sandstone. Again, many species have short ranges, so that each formation has its characteristic fauna. Some, indeed, are long ranged, but these are mainly the simple, smooth-shelled forms difficult of differentiation.
Since 1901 the senior writer has been engaged in the compilation of an illustrated bibliographic index and synonymic catalogue of fossil Ostracoda, primarily as an aid to his studies of this group of organisms. During a part of the time he had the efficient aid of Margaret Moodey, of the Department of Geology of the National Museum, whose work has been of great value in this as well as in other branches of paleontology. Through her assistance the catalogue of Ostracoda was kept fairly well up to date.
In 1928, while a graduate student at the University of Kansas, Betty Kellett, under the guidance of Raymond C. Moore, collected references to fossil Ostracoda and assembled all the titles upon. . . .