108 RESEARCH IN CHINA. 
lateral angle of the pygidium. The central axis has a length of 10 mm., with a 
width at the anterior end of 6 mm., and at the posterior terminal lobe of 6 mm., 
narrowing slightly at the second and third rings; it is divided by three shallow, 
rounded, transverse furrows into three slightly convex rings and a terminal ring 
nearly as long as the two posterior rings; there is also a narrow anterior ring that 
connected the pygidium with the thorax; the terminal ring is convex and slightly 
overhangs the margin; a node or slight swelling is indicated on each side of the 
median line where the ring slopes abruptly down to the margin. Dorsal furrow 
rounded and somewhat irregular. 
Pleural lobes slightly narrower than the axis and arching from the dorsal 
furrow directly down to the border; the lobes are divided by three broad furrows 
into an anterior, marginal, elevated rim and two slightly concave segments; a third 
and posterior segment is indistinctly outlined; the furrows and segments terminate 
within a slightly thickened border. ‘Three pairs of short spines occur on the border 
opposite the two anterior segments and frontal rim of the pleural lobe; opposite the 
faintly defined posterior segment there is a long, strong spine, and from the space 
between the latter spine and where the dorsal furrow intersects the border there is 
another longer and stronger spine that extends obliquely outward and backward. 
The surface is marked by a few pustules that occur on the elevated portions 
of the rings of the axis and the pleural lobes; under a strong lens the crust appears 
to be slightly roughened and apparently minutely punctate. 
Length of pygidium, 11 mm.; width at the anterior border, 16 mm.; width of 
axis, 6 mm.; width of pleural lobe at anterior portion, 5 mm. 
In general outline this pygidium is somewhat like that of Dorypyge richthofeni 
Dames. It differs in the proportionately broader axis, narrower pleural lobes, and 
the pair of strong spines at the postero-lateral angle. 
The pygidium of Dorypyge danica Grénwall [1902, plate 3, fig. 12] has two large, 
long posterior spines on each side next to the axis, also three short spines anterior 
to the long spines, as in D. bispinosa. The two species are quite unlike in their 
other characters. 
Formation and Locality—Middle Cambrian: (C2) Lower shale member of 
the Kiu-lung group [Blackwelder, 1907a, pp. 37 and 4o (part of the third list of 
fossils), and fig. 10 (beds 4 and 5), p. 38], 2 miles (3.2 km.) south of Yen-chuang, 
Sin-t’ai district, Shan-tung, China. 
Collected by Eliot Blackwelder. 
Dorypyge richthofeni Dames. 
Plate 8, Figures 1, 1a-f. 
Dorypyge richthofent DAMES, 1883, China, Richthofen, vol. 1v, p. 24, plate 1, figs. 1-6. (Species 
described and discussed.) 
Doctor Dames gives a detailed description of this species. The new material 
in the Carnegie Institution of Washington collection shows that the pleural lobes 
of the thoracic segments have a rounded, straight groove as in Olenoides; also that 
a spine occurs at the center of the axial lobe, as in Olenoides. 
The specimens described by Doctor Dames were from Ta-ling and Wu-lo-pu. 
In Manchuria the stratigraphic range of this species as now known is confined 
to the shales and interbedded limestones just above the white quartzite sandstone at 
the base of the section. 
Formation and Locality.—Middle Cambrian: (C19) Uppermost layers of the 
Ch’ang-hia limestone [Blackwelder, 19074, p. 33 (part of last list of fossils), at 
