134 RESEARCH IN CHINA. 



Ptychoparia ? tolus Walcott. 

 Plate 12, Figure 13. 



Ptychoparia tolus WALCOTT, 1905, Proc. U. S. Nat. Mus., vol. xxix, p. 82. (Described as in first 

 paragraph below.) 



Of this species only a single, fragmentary cephalon in known; this is much 

 like the corresponding parts of the cephalon of Anomocarella thraso, but it differs 

 (a) in being less convex, (6) in having a more coarsely granulated surface, (c) stronger 

 posterior glabellar furrows, (d) broader fixed cheeks, and (e) more broadly rounded 

 front to the glabella. The length of the cephalon is 10 mm. ; of the glabella, 7 mm. ; 

 width of the cephalon, including palpebral lobes but not fixed cheeks, 12 mm. 



The strong granulation on the surface indicates that P. ? tolus will be found to 

 belong to some other genus than Ptychoparia when the entire dorsal shield is known. 



Formation and Locality. Middle Cambrian: (C52) In the lower part of the 

 limestone member of the Kiu-lung group [Blackwelder, 19070, pp. 37 and 39 (second 

 list of fossils), and fig. 7 (bed 22), p. 27], near base of cliffs in mountain i.ooofeet 

 (305 m.) high, 3 miles (4.8 km.) north-northeast of Sin-t'ai-hien, Shan-tung, China. 



Collected by Eliot Blackwelder. 



Ptychoparia typus (Dames). 

 Plate 12, Figures 14, 140-1;. 



Conocephalites typus DAMES, 1883, China, Richthofen, vol. iv, p. n, plate 2, figs, n, 12. (Described 

 and figured.) 



Of this species only the central portions of the cephalon and pygidium are 

 known. These were described and illustrated by Doctor Dames and in this paper 

 examples from the shale are figured. 



Formation and Locality. Middle Cambrian: (35 o) 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 in drainage cuts a short distance 

 back from the bluff [see 35 n] forming the shore of Tschang-hsing-tau Island, 

 east of Niang-niang-kung, Liau-tung, Manchuria, China. 



Collected by J. P. Iddings and Li San. 



EMMRICHELLA Walcott, subgenus of PTYCHOPARIA. 



Emmrichella WALCOTT, 191 1, Smithsonian Misc. Coll., vol. 57, No. 4, p. 79. (Described and discussed 

 as a new genus essentially as below.) 



This subgenus differs from Ptychoparia in its smooth glabella and larger pal- 

 pebral lobe; from Liostracus in having an arched or nearly flat frontal limb and 

 rim and more convex cranidium; from Conokephalina in its smoother glabella 

 and wider fixed cheeks; and from Anomocare in its smoother glabella, usual absence 

 of distinct palpebral ridge, and proportionately shorter eye-lobes and glabella. 



Genotype. Ptychoparia theano Walcott. 1 



This subgenus is characterized by a nearly smooth surface on the glabella 

 and fixed cheeks, rather large palpebral lobes, and narrow postero-lateral limbs. 

 Unfortunately, no entire specimens of the cephalon and thorax are known, and the 

 pygidia referred to it may or may not belong to the species to which they are tenta- 

 tively assigned. Only when a thorough study is made of all the material within 

 the Conokephalinae will it be possible to make even a fairly adequate grouping of 

 the species. 



'Walcott, 19056, Proc. U. S. Nat. Mus., vol. 29, p. 82; Idem, 1911, Smithsonian Misc. Coll., vol. 57, No. 4, 

 plate 14, figs. 9 and ga. 



