Cambrian Geology and Paleontology No, Vol. 1: Trilobites, With Six Plates (Classic Reprint)

Order PROPARIA Beecher BuRL iNG iD.li, new family Dorsal shield small, elongate, broad oval in outline. Cephalon about one-fourth the length, transversely semicircular; genal angle acute or spinose; glabella with transverse lobes. Free cheeks small, separate. Facial sutures cut the margin in front of the genal angles, extend in to the posterior portion of the eye lobe and outward from the anterior portion to the antero-lateral margin of the cephalon. Eyes of medium size, clearly defined. Thorax with fourteen segments in the one species preserving them ;pleurae with flat, straight furrows. Pygidium large, with strong axis and pleural lobes, or small and with medium axis and pleural lobes. Stratigraphic Range. Central portion of theM iddle Cambrian to the A gnostiis pisiformis zone of theS wedish Upper Cambrian. Observations, This family includes the genera Burlingia andS chmalenseeia} The first is represented by entire specimens and the latter by the cephalon, fragments of the thorax, and entire pygidia. The facial sutures and free cheeks relate Burlingia to some forms of the Cheiruridae, while the pygidium of Burlingia recalls the simple pygidium of Paradoxides, and the pygidium of Schmalenseeia recalls that of A mphion. The flat, straight furrowed pleurae of the thorax of Burlingia recall the pleurae ofO lenoides. The assemblage of characters in Burlingia andS chmalenseeia clearly indicate a distinct family of the Proparia, more primitive than any other forms of that order. BURLINGIA, new genus Dorsal shield small, elongate, broadly oval. Cephalon semicircular ;one-fourth the length of the entire shield; genal angles with spines; cranidium with anterior and posterior limbs that extend outward from the glabella to the outer margin; glabella slightly convex, with indications of lobes. Free cheeks subquadrangular, small. Facial sutures extend from in front of
(Typographical errors above are due to OCR software and don't occur in the book.)