On 6 October 1764, Adriaan Vroeg sold his collection of birds, insects and a few other animals by auction. The sales catalogue was published anonymously, but contained several scientific names of birds, which have nomenclatorial standing. Only three copies of this catalogue are known. The appendix entitled “Adumbratiunculae” has previously been attributed to Peter Simon Pallas, who is quoted as author of the new names of birds. In the present note, the main text is credited to Arnout Vosmaer, on the basis of contemporary references. Where the species names proposed by Vosmaer are synonyms of those published by Pallas in the same volume, the latter are selected, because some names have been validly used before with Pallas as the author.