3014 20170106115608.0 10.1007/s11207-016-0905-2 DOI SCART-2017-0010 Lefèvre, L. An Early Sunspot Catalog by Miguel Aguilar for the Period 1914 - 1920 2016 Sunspot Number special Issue We provide a source of detailed solar parameters spanning the years 1914 - 1920. Although various catalogs containing information on sunspots and sunspot groups have been available for almost 150 years, the contents and conventions can vary greatly from one source to another. Thus, the availability of multiple sources is very important to assess the relative uncertainties in the identified quantities. We provide here a machine-readable version of the sunspot catalog made by M. Aguilar from 1914 to 1920. We show and explain the structure and possible errors found in this catalog. We also try to understand the specific differences of this catalog, i.e. explain the shortcomings and benefits of this catalog versus other available sources of solar information. This catalog, combined with the Valencia catalog, presents a valuable source of comparison with the Royal Greenwich Observatory (RGO or GPR for Greenwich Photoheliographic Results) data, and it helps shed more light on the link between the RGO classification and the more modern classifications of sunspot groups found in the Zürich or McIntosh classifications. We also extend the work started by Carrasco et al. ( Solar Phys. 290, 1445, 2015) on the mapping of Cortie types. STCE Catalogs Sunspots Morphological classification of sunspots Cortie classification Zurich classification RGO classification Aparicio, A. J. P. Gallego, M. C. Vaquero, J. M. Solar Physics 291 2016 9-10 2609-2628 laure.lefevre@observatoire.be published in REFERD