A Monograph of the Trilobites of North America: with Coloured Models of the Species

Every author who attempts a Monograph of any of the departments of Natural History, must necessarily depend, in a greater or less degree, upon the kindness and liberality of others. Rare and unique specimens, particularly of fossil species, are often scattered through different cabinets, and his work would be rendered very imperfect, if they were not intrusted to his care. In preparing the following Monograph on the plan of giving exact models of the species, instead of illustrating them by engravings in the usual manner, the specimens when used by the artist are perhaps more liable to accident, and it was at first supposed that this circumstance might have prevented the original design. But in no instance, where an application has been made, either to a public institution or to a private cabinet, has the author met with a refusal; indeed the courtesy, kindness, and liberality which he has experienced from naturalists, who have every where aided him in the prosecution of his work, form no inconsiderable portion of the gratification which he has received. Besides the acknowledgments to public museums, and to individuals, which are made in the body of the work, the author is desirous of recording in this place, the following cabinets from which he has derived much assistance.