. On the Cambrian faunas of North America [microform] : preliminary studies. Paleontology; Arthropoda, Fossil; Arthropoda, Fossil; Paléontologie; Arthropodes fossiles; Arthropodes fossiles. WALCOTT. I FAUNA OF THE SAINT JOHN FORMATION. 39 To me the distinctive (jharacter between this species and P. ouangon- (liana is in the form of the glabella. Compression and distortion may give the depressed broader form and reflexed rim, but not entirely the subquadrate glabella, that appears to be a feature of original varietal importance. With a large series of specimens of this form showing its variati
. On the Cambrian faunas of North America [microform] : preliminary studies. Paleontology; Arthropoda, Fossil; Arthropoda, Fossil; Paléontologie; Arthropodes fossiles; Arthropodes fossiles. WALCOTT. I FAUNA OF THE SAINT JOHN FORMATION. 39 To me the distinctive (jharacter between this species and P. ouangon- (liana is in the form of the glabella. Compression and distortion may give the depressed broader form and reflexed rim, but not entirely the subquadrate glabella, that appears to be a feature of original varietal importance. With a large series of specimens of this form showing its variations, the tendency will be to deprive it even of a varietal name and unite it directly with P. Ouangondiana. Formation and locality.âWith the preceding species at Katcliflfs Mill- stream, N. B. Ptychoparia qitadrata, Hartt. Plate V, lig. 1. ConocephalUea quadrata, Hartt, 1868, Acauian Geology, Dawson, 2d ed., p. 654. Description.â"Head minute, transversely oblong, twice as long, slightly curved in front, straight behind, very flat; a narrow elevated fold, convex in front, concave behind, and somewhat inclined backward, goes round the ; There appears to be but one specimen representing this species in the collection. The strongly-marked subquadrate glabella distinguishes it at once from the associated species except P. ouangondianus, var. au- rora, from which it is Si^arcely separated by the character of the frontal rim and the stronger ocular ridges. The entire length of the head is but two millimeters. Formation and locality.âCambrian. Saint John formation. Portland, a little northward of Saint John, N. B. Ptychopaeia Orestes, Hartt. Plate V, fig. 3, 3a. Conoceplialitea orestes, Hartt, 1868, Acadian Geology, ^son, 2d eil., p. 649, Conocephalitea Halli, Hartt, 1868, Acadian Geology, Dawson, 2d ed.,p. 654. Description,â" The head-shield of this species without movable chee'ko is of medium size, length about equal to breadth in front, or to two- tbir
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