204 RESEARCH IN CHINA. 
strong, rounded furrow that terminates in the dorsal furrow beside the glabella. 
Cranidium with the front broadly rounded, narrow fixed cheeks, small antero-lateral 
limbs, and narrow postero-lateral limbs, the greater part of which is taken up by the 
strong intermarginal furrow. Glabella without traces of transverse furrows except 
a short, slight indentation indicating a posterior pair of furrows; the glabella is 
separated from the fixed cheeks by a very narrow, strong dorsal furrow; the frontal 
limb has about the same width as the frontal margin, and extends almost directly 
downward from the dorsal furrow in front of the glabella to the sharp angle made 
by its union with the frontal margin; fixed cheeks about one-third the width of the 
glabella opposite the palpebral lobes, gently convex and merging into the anterior 
and posterior limbs; occipital ring separated from the glabella by a strong rounded 
furrow; it is convex, broad along the center portions and narrow toward the dorsal 
furrow. Palpebral lobe small, elevated, and about one-fourth the length of the 
cephalon; a low ridge extends from its anterior end forward and inward to the dorsal 
furrow beside the glabella. Free cheeks small, gently convex, and bordered by a 
flattened rim that is continued posteriorly into a spine; they are separated from the 
cranidium by the facial sutures, which cut the posterior margin a short distance 
within the genal angles and extend with a slight sigmoid curve inward and forward 
to the base of the palpebral lobes; curving around these they extend with a slight 
outward curvature to the angle formed by the union of the frontal limb and margin, 
and then curve slightly inward across the margin. 
Thorax with twelve rather narrow, nearly transverse segments; axial lobe 
convex, with the segments slightly rounded and separated from the pleural lobes by 
the obtuse angle formed by the union of the two lobes; pleural lobes a little wider 
than the axial lobe and flattened for about half their width or to the geniculation, 
where each segment curves downward and slightly backward; pleural furrow rel- 
atively broad; it starts near the inner anterior edge of the pleural segment and 
extends along the center of the segment to the geniculation, where it gradually 
narrows to a point near the end of the flattened falcate termination of the segment. 
Pygidium small; the subconical convex axis is marked by three shallow trans- 
verse furrows that outline three rings and a terminal section that terminates within 
a short distance of the posterior margin of the pygidium; pleural lobes marked by 
the extension of the transverse furrows on the axial lobe and the faintly indicated, 
rather narrow border. 
Surface slightly roughened by shallow pits or a network of very minute, irreg- 
ular ridges, the interspaces of which give a pitted appearance. 
Dimensions.—There are nine entire specimens of the dorsal shield, exclusive of 
the free cheeks. The average length is 15 mm. ‘The different parts have the 
following dimensions. 
Cephalon: mm. 
Length 3... 6Gs ds ofS dc bee 6 ae ee Oe ee eee nae 6.5 
Width at posteriorimargist. cance see eee a ete eee cies ates ee aot ete 9.0 
Length ol/glabellaatid occipital rngoenmreer ren eect 30 
Width: of, glabella‘at: based... eee eee eens Ceteeietrae 3.5 
‘Thorax: 
Lengthy etait Oey OP ai ren re ee peece leer 7 host 
Width at: first segments. nccrcaeeiiecei rt Cee nei aie 8.0 
Widthat last segment i727. pees See eae tee eee 5.0 
Pygidium: 
TON gth oy oes oe os coe a bcsin es ee eh Ce Rene ole es See ee eee 2.0 
Widthtatianterior margin Vea. aoe ee ine acre ie eae 4.5 
