The Appendages, Anatomy, and Relationships of Trilobites

by Percy E. Raymond

Plates [1]-[5]. Photographs of Triarthrus becki, made by C. E. Beecher.

Plate [6]. Photographs of Triarthrus becki (figs. 1-3), Acidaspis trentonensis (fig. 6), and Cryptolithus tessellatus (fig. 7), made by C. E. Beecher. Photographs of the endopodites of a probable species of Calymene (figs. 4, 5)

Plates [7]-[8]. Photographs of Cryptolithus tessellatus, made by C. E. Beecher.

Plate [9]. Drawings of Cryptolithus tessellatus, made by C. E. Beecher or under his direction.

Plate [10]. Photographs of Isotelus latus and I. maximus, made by C. E. Beecher.

Plate [11]. Drawing of a restoration of Ceraurus pleurexanthemus, made by Elvira Wood.

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HISTORICAL REVIEW.

The beginning of the search for the limbs of trilobites was coeval with the beginning of scientific study of the group, knowledge of the appendages being essential to the proper systematic allocation of the animals.