Bregmaceros mcclellandi Thompson, 1840

This archival ledger page documents a specimen of *Bregmaceros mcclellandi*, a deep-sea fish species. The handwritten entries record taxonomic data, measurements, and collecting information in the meticulous style of natural history curation. Such scientific catalogs represent the systematic documentation practices that shaped modern taxonomy and museum collections during the early twentieth century, when ichthyological study was advancing through institutional networks and specimen exchange. These records—combining precise notation with occasional marginal annotations—reveal how museums transformed individual discoveries into organized knowledge systems that remain foundational to zoological science today.