Scientists, in classifying invertebrate palaeontology, are obliged by the nature of the research to compare findings with illustrations and previous studies found in works dating back many decades. These classic works, when obscure or out of print, are difficult to obtain. To accommodate the needs of palaeontologists, Classic Literature on Invertebrate Palaeontology offers, on microfiche, material selected by specialists in seven major macro-invertebrate groups. Chosen are key materials, primarily from the 19th and early 20th centuries, and articles published in now-defunct journals or as monographs. These works include many of the first descriptions given of important species and contain numerous detailed illustrations.