70 RESEARCH IN CHINA. 



relatively broader in outline, with the sides of the valves less uniformly arched, 

 and in having a more broadly rounded frontal margin. 



Interiors of the ventral valve indicate that the area was relatively shorter 

 than that of L. similis (Walcott) [19126, plate xxi, figs. 2, 2a-j, 3, ^a-d]. Most of 

 the shells in the limestone are less than 2 mm. in length ; a few ventral valves in the 

 shale are 3 to 5 mm. long. 



Formation and Locality. Middle Cambrian: (35 q and 36 h) Fu-chou series; 

 about 200 feet (61 m.) above the white quartzite; also in shales about 130 feet 

 (40 m.) above the white quartzite [see Blackwelder, 19076, p. 92, for general section 

 showing stratigraphic relations] ; collected in 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. 



A form flattened in the shale of Locality 36 f, which is much higher but in the 

 same section as the locality represented by L. mar da, has the outline of the latter 

 species and is tentatively referred to it. This gives an extended stratigraphic 

 range for the species, but not so great as L. similis (Walcott) [19126, pp. 532-534], 

 which occurs in both the Middle and Upper Cambrian. 



LINGULEPIS Hall, subgenus of LINGULELLA. 



For discussion of subgenus Lingulepis see Monogr. U. S. Geol. Survey, vol. LI, 

 1912, pp. 544-545- 



Lingulella (Lingulepis) eros (Walcott). 

 Plate 3, Figures 2, 20. 



Obolus (Lingulepis) eros WALCOTT, 1905, Proc. U. S. Nat. Mus., vol. xxvm, p. 333. (Described and 



discussed as below as a new species.) 

 Lingulella (Lingulepis) eros (WALCOTT), 1912, Monogr. U. S. Geol. Survey, vol. LI, p. 551, plate xxxix, 



figs. 9 and 90. (A copy of the preceding reference.) 



Ventral valve elongate with rostral slopes gradually converging so as to form 

 an acuminate beak. Surface marked by fine, concentric lines of growth and very 

 fine, somewhat irregular, concentric striae. Rather large, scattered punctse occur on 

 the interior surface. 



This species is represented by fragments and two broken ventral valves; these 

 indicate a length for the ventral valve of 7 to 10 mm. 



It is allied to Lingulepis acuminatus meeki (Walcott) 1 of the Middle Cambrian 

 fauna of the Teton Mountains of Wyoming. 



Formation and Locality. Middle Cambrian: (C7) Lower limestone member 

 of the Kiu-lung group [Blackwelder, 19070, pp. 37 and 39 (last list of fossils), and 

 fig. 8a (bed 33), p. 29], 2.2 miles (3.5 km.) southwest of Yen-chuang, Sin-t'ai district, 

 Shan-tung, China. 



Collected by Eliot Blackwelder. 



Lingulella (Lingulepis?) sp. undt. (Walcott). 



Obolns (Lingulepis ?) sp. undt. WALCOTT, 1906, Proc. U. S. Nat. Mus., vol. xxx, pp. 567-568. (Char- 

 acterized as on page 71 as an independent species.) 



Lingulella (Lingulepis) sp. undt. (WALCOTT), 1912, Monogr. U. S. Geol. Survey, vol. Li, p. 560, plate 

 xxxix, figs. 9 and 90. (A copy of the preceding reference.) 



^Lingulepis meeki Walcott, 1897, Am. Jour. Sci., 4th ser., vol. HI, p. 405. 



