22O RESEARCH IN CHINA. 



elevated, and separated from the fixed cheek by strongly defined furrow; the palpe- 

 bral lobes are narrow and a little less than one-fourth the length of the cephalon. 

 Genal angles extended into short, sharp, backward-curving spines. The cranidium 

 is broad at the base, narrowing toward the front; the antero-lateral limbs are very 

 small and disappear where the palpebral lobe touches the dorsal furrow ; the postero- 

 lateral limbs and narrow fixed cheeks merge into each other so as to form trans- 

 versely subtriangular areas, with the narrow palpebral lobes on their front outer 

 margins. 



Glabella large, subquadrangular in outline, and separated from the fixed cheeks 

 by clearly defined dorsal furrows; its sides are nearly parallel or slightly diverging; 

 front broadly rounded, almost transverse; surface marked by five pairs of furrows, 

 the posterior of which extends obliquely across the posterior portion nearly to the 

 center and separates a small triangular lobe on each side; the next two anterior 

 pairs of furrows are short and extend inward at right angles to the side of the 

 glabella; the anterior pair is nearly opposite the front end of the palpebral lobe; 

 the anterior furrows are short and extend obliquely inward subparallel to the front 

 margin of the glabella. Occipital ring narrow at the sides, widening toward the 

 center, where it is marked by a small sharp node a little back of the transverse 

 center. Free cheeks large and surmounted on the inner side by a narrow eye-lobe. 

 The facial sutures cut the posterior margin a little within the genal angle and extend 

 obliquely inward and lightly forward to the base of the eye-lobes; curving over 

 and around the eye-lobes, they extend forward and downward, cutting the front 

 margin on a line with the posterior base of the eye-lobe. Number of thoracic seg- 

 ments unknown. Single specimens of the segments show that the axial lobe was 

 nearly as wide as the pleural lobes, that it was moderately convex, and that a small 

 node occurs at the center of each segment near the posterior margin ; also that on 

 the outer side of each segment a rounded transverse node is outlined from the main 

 body of the segment by a slightly oblique transverse furrow; pleural lobes nearly 

 flat out to the geniculation, where they curve gently downward; each pleura has a 

 furrow that is broad at its inner end next to the axial lobe and gradually narrows 

 to the geniculation, where it terminates within the somewhat broadly rounded outer 

 extremity; in well-preserved specimens a rounded ridge starts near the inner end 

 of the pleural furrow and extends outward one-fourth of the length of the furrow. 



The associated pygidia are semicircular, with the anterior margin almost trans- 

 verse in the compressed specimens. The axial lobe is large and quite distinctly 

 marked; it is divided by three transverse furrows into three rings and a terminal 

 section that ends posteriorly just within the outer border ; a small node occurs near 

 the posterior margin at the center of each ring; five anchylosed segments are out- 

 lined on the pleural lobes by furrows that progressively curve more and more back- 

 ward from the first to the posterior one, which adjoins the terminal segment ; the 

 furrows all terminate within the narrow, slightly flattened border. 



The casts of the outer surface indicate that it was smooth or minutely granulose. 



This species appears to be quite distinct from any that has been described. 

 The quadrangular glabella with nearly parallel sides distinguishes it from Bathy- 

 uriscus howclli Walcott [18.86, plate 30] and P>. proditctiis Hall and Whitfield [idem, 

 fig. i], which is illustrated on the same. 



Formation and Locality. Middle Cambrian: (35 o, 3(5 g, and 3(5 h). Fu-chou 

 series, shales about 130 feet (40 m.) above the white quartzite [see Blackwelder, 

 19076, p. 92, for general section giving stratigraphic relations] ; collected near a low- 

 bluff on the shore of Tschang-hsing-tau Island, east of Niang-niang-kung, Liau- 

 tung, Manchuria, China. 



Collected by J. P. Iddings and Li San. 



