Lorentz Spengler's descriptions of chitons (Mollusca: Polyplacophora)

The present paper deals with an important Danish paper on the Polyplacophora, published in 1797 by Lorentz Spengler: Udförlig Beskrivelse over det mangeskallede Konkylie-Slaegt, af Linnaeus kaldet Chiton; med endeel nye Arter og Varieteter. -Skrivter af Naturhistorie-Selskabet, 4e Bind, Ie Hefte, VI: 62-103, Tab. VI (Kiöbenhavn). In order to make this historical paper accessible to students of the group, a translation (by Dr J. Knudsen, with the assistance of the late Mrs A. Volsoe) of the original 18th century Danish text into modern English is here presented. A considerable part of the material in the "Museo Spengleriano", on which Spengler based his descriptions, is still extant, being held now in the Zoological Museum, University of Copenhagen. The translated description of every species and/or variety is followed by annotations in a smaller font (by P. Kaas) on the available specimens, including a discussion on their current taxonomic status. Spengler described 27 species and 10 varieties of chitons. He introduced 16 new taxa, of which 6 names are still valid.