154 RESEARCH IN CHINA. 



Surface finely punctuate under a strong lens. The largest cephalon in the col- 

 lection has a length of 6 mm. 



This species is characterized by the tumid frontal limb and the ridge within 

 the palpebral lobe on the fixed cheek. 



Formation and Locality. Middle Cambrian : (C 70) Oolitic limestone about 30 

 feet (9 m.) above the base of the Ki-chou limestone [Willis and Blackwelder, 1907, 

 p. 144 (last list of fossils)], 4 miles (6.4 km.) south-southwest of Tung-yu, Shan-si, 

 and (CIS) limestone near the base of the Ki-chou formation [idem, p. 143], 4.5 

 miles (7.2 km.) south of Wu-t'ai-hien, Shan-si, China. 



Collected by Eliot Blackwelder. 



Inouyia ? regularis (Walcott). 

 Plate 14, Figure 18. 



Agraulos regularis WALCOTT, 1906, Proc. U. S. Nat. Mus., vol. xxx, p. 578. (Species described essen- 

 tially as below.) 



This species is represented by a few specimens of the central portions of the 

 cephalon, exclusive of the free cheeks. These indicate that the cephalon was rather 

 strongly convex, and semicircular in outline. Glabella convex, truncato-conical, 

 rounded in front, and with traces of two pairs of short glabellar furrows that divide 

 it into three subequal portions ; occipital furrow narrow but clearly defined ; occip- 

 ital ring narrow at the sides, increasing slightly in width toward the center, where 

 it rises to form the base of a small node; dorsal furrow deep and rather broad. 



Fixed cheeks convex, rising abruptly from the dorsal furrow, the posterior 

 furrow of the cephalon, and the anterior margin; in front they merge into the 

 rounded, convex frontal limb with a trace of an intervening furrow and narrow 

 palpebral ridge; palpebral lobes small and situated opposite the central portion 

 of the glabella. 



Surface, under a strong lens, shows traces of being very finely punctate. The 

 average length of three specimens of the cephalon is 2 mm. 



The cephalon representing this species has the rounded, full fixed cheeks and 

 frontal limb of Inouyia f acalle [p. 150], but it differs in having a proportionately 

 shorter and broader glabella, and in being broader between the facial sutures. 



Formation and Locality. Middle Cambrian: (073) Conglomeritic limestones 

 near the top of the Ki-chou limestone [Willis and Blackwelder, 1907, p. 145 (fourth 

 list of fossils)], 4 miles (6.4 km.) east of Fang-lan-chon, Shan-si, China. 



Collected by Eliot Blackwelder. 



Inouyia thisbe Walcott. 



Plate 14, Figure 21. 



Inouyia ? thisbe WALCOTT, 1911, Smithsonian Misc. Coll., vol. 57, No. 4, p. 81, plate 14, fig. 14. 

 (Described and discussed as a new species essentially as below.) 



This species is represented by two broken specimens of the cranidium. These 

 show that the glabella is much like that of Inouyia titiana (Walcott) [plate 14, 

 fig. 9] ; also the fixed cheeks and palpebral lobes. It differs in the transverse swelling 

 of the frontal limb. In /. thisbe the frontal limb rises with a slight slope in front 

 of the glabella, and curves gently downward to the margin without a trace of a 

 frontal border as in Inouyia inflata (Walcott) [plate 14, fig. 10]. In /. titiana the 

 frontal limb is abruptly convex and there is an almost flattened border. 



The surface of /. thisbe is distinctly punctate and in this respect resembles 

 Agraulos dryas [plate 14, fig. 20]. 



The type specimen of the cranidium has a length of 5.5 mm. 



