DESCRIPTION OF PLATE 22. 
Dolichometopus deois Walcott [see plate 21, figs. 13, 13a—d] (p. 216). 
1. Dorsal view and side outline of a cranidium, X 2, from Locality C1, Middle Cambrian, Kiu-lung 
group, 2 miles (3.2 km.) south of Yen-chuang, Shan-tung. U.S. Nat. Mus., Cat. No. 58240. 
1a. Free cheek, X 3, associated with fig. 1b. U.S. Nat. Mus., Cat. No. 58241. 
1b. Dorsal view and side outline of a cranidium, X 2. (C57.) U.S. Nat. Mus., Cat. No. 58242. 
1c. Hypostoma, X 3, associated with the specimen represented by fig. 1b. (C57.) U.S. Nat. Mus., 
Cat. No. 58243. 
1d and 1e. Nepionic stages, X 15, in the development of a trilobite, probably of this species. (C57.) 
U. S. Nat. Mus., Cat. Nos. 58244 and 58245. 
1f. A cranidium (X 10) of a young individual associated with specimen represented by fig. 1b. (C57.) 
U.S. Nat. Mus., Cat. No. 58246. 
1g. Thoracic segment, X 3, associated with specimen represented by fig. 1b. (C57.) U.S. Nat. Mus., 
Cat. No. 58247. 
The specimens represented by figs. 1a-g are from Locality C57, Middle Cambrian, Kiu-lung group, 
south of Kao-kia-p’u, Shan-tung. 
1h. Pygidium, natural size, from Locality C4, a little below the layer from which specimen represented 
by fig. 1 was collected. U.S. Nat. Mus., Cat. No. 58248. 
2. Photograph (X 1.5) of one of the fragments of limestone collected by Dr. Th. Lorenz at Wang- 
tschuang, Shan-tung. The pygidia were referred to Bathyuriscus asiaticus Lorenz, by Lorenz, 
and the cranidia on the other side of the same piece of limestone to the same species. [Lorenz, 
1906, plate v, figs. 1-5.] U.S. Nat. Mus., Cat. No. 58538. 
2a and 2b. Cranidia on the opposite side of the piece of limestone illustrated by fig. 2. U.S. Nat. Mus., 
Cat. No. 58539. 
Dolichometopus alceste Walcott (p. 215). 
3. Type specimen showing parts of cranidium in front of occipital furrow; with side outline of same, X 2. 
From Locality C4, Middle Cambrian, Kiu-lung group, south of Yen-chuang, Shan-tung. 
U.S. Nat. Mus., Cat. No. 58249. 
3a. Free cheek associated with this species at Locality C4. U.S. Nat. Mus., Cat. No. 58250. 
3b. Pygidium associated with this species a little lower in the section (C1). U.S. Nat. Mus., Cat. No. 
58251. 
Dolichometopus derceto Walcott (p. 217). 
4. Type specimen showing portions of the cranidium; and side outline of same, X 3. From Locality 
C1, Middle Cambrian, Kiu-lung group, south of Yen-chuang, Shan-tung. U.S. Nat. Mus., 
Cat. No. 58252. 
4a. Fragment of a pygidium from C2, just above the locality of specimen represented by fig. 4. U.S. 
Nat. Mus., Cat. No. 58253. 
Dolichometopus dirce Walcott (p. 218). 
5. Type specimen showing central parts of cranidium; and side outline of same, X 2. From Locality 
C24, Middle Cambrian, Ch’ang-hia formation, east of Ch’ang-hia, Shan-tung. U.S. Nat. 
Mus., Cat. No. 58254. 
5a. Large free cheek (natural size) associated with specimen represented by fig. 5. U.S. Nat. Mus., 
Cat. No. 58255. 
5b. Small pygidium associated with specimen represented by fig. 5, X 4. U.S. Nat. Mus,, Cat. No. 
58256. 
Dolichometopus hyrie Walcott (p. 218). 
6. Type specimen showing central parts of cranidium; and side outline of same, X 3. From Locality 
C69, Middle Cambrian, Ki-chéu limestone east of Fang-lan-chén, Shan-si. U.S. Nat. Mus., 
Cat. No. 58257. 
6a. Associated free cheek, X 2. U.S. Nat. Mus., Cat. No. 58258. 
6b. Associated pygidium. Natural size. U.S. Nat. Mus., Cat. No. 58259. 
Bathyuriscus ? sp. undt. Walcott. 
7. Asmall, smooth pygidium from Locality C28, Middle Cambrian, base of the Ch’ang-hia limestone, 
1 mile (1.6 km.) east-southeast of Ch’ang-hia, Shan-tung. U.S. Nat. Mus., Cat. No. 58264. 
Bathyuriscus ? ? sp. undt. Walcott. 
8. Small pygidium from Locality C68, Upper Cambrian, Ch’au-mi-tién limestone near Ch’au-mi-tién, 
Shan-tung. U.S. Nat. Mus., Cat. No. 58265. 
Hysterolenus ? spp. undt. Walcott [see plate 23, fig. 9] (p. 219). 
9. Dorsal and side views of a large specimen of pygidium. From Locality C38, Upper Cambrian, 
Ch’au-mi-tién limestone, at Ch’au-mi-tién, Shan-tung. U.S. Nat. Mus., Cat. No. 58266. 
9a. Dorsal view of small pygidium, X 4. From Locality C56, Upper Cambrian, Ch’au-mi-tién lime- 
stone west of Tsi-nan, Shan-tung. U.S. Nat. Mus., Cat. No. 58267. 
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