130 RESEARCH IN CHINA. 
been determined. Doctor Monke compares Drepanura with Teinistion and the 
Scandinavian genera Acerocare and Peltura. 
Formation and Locality.—Middle Cambrian: (C6) Thin, platy limestone in 
the upper shale member of the Kiu-lung group [Blackwelder, 1907a, pp. 37 and 
41 (second list of fossils), and fig. 10 (bed 12), p. 38], 2.5 miles (4 km.) southwest of 
Yen-chuang, Sin-t’ai district, Shan-tung; and (C55), just below the Ch’au-mi-tién 
limestone in the Ku-shan shales [idem, p. 43], in isolated hills at an elevation of 
380 feet (114 m.) above the Woén-ho, 12 miles (19 km.) south 80° east of Tsi-nan, 
Shan-tung, China. 
Collected by Bailey Willis and Eliot Blackwelder. 
Also from (36f), Fu-chéu series; about 1,000 feet (305 m.) above the white 
quartzite [see Blackwelder, 1907), p. 92, for general 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. 
Genus PTYCHOPARIA Corda. 
Ptychoparia Corba, 1847, Prodrom einer Monographie der b6hmischen Triboliten, p.141. (Proposes 
Ptychoparia for generic group of trilobites represented by Conocephalites striatus Emmrich and 
gives diagnosis of genus.) 
Ptychoparia Corda, WaucoTT, 1884, Bull. U. S. Geol. Survey No. 10, On the Cambrian Faunas of 
North America, pp. 34-36. (Compares and discusses genus.) 
Ptychoparia Corda, LORENZ, 1906, Zeitschr. deutsch. geol. Gesellsch., vol. Lv1m, pt. 2, p. 57. (Quotes 
Corda’s diagnosis and adds ‘‘dense shell structure” as a generic character.) 
Many authors have referred to the genus Ptychoparia. I will not enter into 
a discussion of it at this time, as I am planning to give the genus more extended 
consideration in connection with the description of a number of new species from 
North America. 
In this memoir the genus is restricted to species having the characteristics of 
Ptychoparia striata Emmrich. One character should be noted. The increase in 
the length of the palpebral lobe from the short lobe of P. striata [plate 12, fig. 4] 
to the proportionately longer lobe of P. kingi [fig. 6] is marked. In P. striata the 
cephalon is four and a half times as long as the palpebral lobe, and in P. kingzi it 
is three times as long. This elongation of the palpebral lobe is continued in Cono- 
cephalites emmricht Barrande [plate 13, fig. 7] and other species grouped under 
Conokephalina. 
In Walcott, 19055 [Proc. U. S. Nat. Mus., vol. xxrx, p. 81], an undetermined 
species of Ptychoparia was described, based on a single specimen of the central por- 
tion of a cephalon, from the Middle Cambrian, Locality C58, upper portion of the 
Ch’ang-hia formation, near the middle of the Ch’ang-hia oolitic limestone, 2 miles 
(3.2 km.) south-southeast of Kao-kia-p’u, Shan-tung. ‘The specimen upon which 
this species was determined was lost or misplaced before the final study of the fauna. 
There is also another undetermined species of Ptychoparia, from Locality C48, 
which shows only the narrow portions of the cranidium and part of a fixed cheek. 
Formation and Locality —Middle Cambrian: (C48) Near the top of the cliffy 
oolitic limestone in the Ch’ang-hia limestone [Blackwelder, 19074, p. 32 (part of last 
list of fossils)], at Ch’au-mi-tién, Shan-tung. 
Ptychoparia aclis Walcott. 
Plate 12, Figures 8, 8a. 
Ptychoparia aclis WALCOTT, 1905, Proc. U.S. Nat. Mus., vol. xxrx, p. 75. (Described as a new species 
as below.) 
Only the slightly convex central portions of the cephalon of this species are 
known. ‘The species is distinguished by the breadth of the glabella in front, and 
