This catalogue lists the spectral classifications of over 3200 stars, mainly of large proper motion, observed and classified by the late Dr. G.P. Kuiper during the years 1937-1944 at the Yerkes and McDonald Observatories. While Kuiper himself published many of his types, and while improved classifications are now available for many of these stars, much of value remains: for a great many of the objects no other spectral data exist.