DESCRIPTION OF GENERA AND SPECIES. I2Q 



Formation and Locality. Middle Cambrian: (35 o) Fu-chou series, shales about 

 130 feet (40 m.) above the white quartzite [see Blackwelder, igojb, 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. 



Genus DREPANURA Bergeron. 



Drepanura BERGERON, 1890, Bull. Soc. gol. de France, 3d ser., vol. xxvn, p. 509. (Describes and 



discusses genus.) 

 Drepanura Bergeron, MONKE, 1903, Jahrb. konigl. Preuss. Geol. Landesanstalt und Bergakademic, 



vol. xxm, pt. i, p. 124. (Discusses genus under the species D. premesnili Bergeron.) 



Both M. Bergeron and Doctor Monke united the description of the genus and 

 the type species. Nothing has been added to our knowledge since Doctor Monke 

 wrote his very full description of D. premesnili, the type of the genus. Doctor 

 Monke described a second species, D. kcttclcri, which differs in the cranidium from 

 that of D. premesnili in having the eye-lobes further back and in details of the 

 glabella and free cheeks, also of the pygidium. [See plate 10, figs. 2, 26, 3, 30.] 



Genotype. Drepanura premesnili Bergeron. 



Drepanura ketteleri Monke. 



Plate 10, Figures 3, 30 c. 



Drepanura ketteleri MONKE, 1903, Jahrb. konigl. Preuss. Geol. Landesanstalt und Bergakademie, vol 

 xxm, pt. i, p. 132, plate 6, figs. 114; plate 9, No. 5. (Described as a new species.) 



This species differs from Drepanura premesnili Bergeron by its strongly gran- 

 ulated test, more convex glabella, the position of the eye-lobes, and many minor 

 details of the cranidium. The pygidium is of the same type as that of D. premesnili, 

 as may be seen by comparing figures 30 and y with 2& and 20, plate 10. Doctor 

 Monke has given a very elaborate description of all known parts and made extended 

 comparisons with D. premesnili. 



Formation and Locality. Middle Cambrian: (C6) Thin, platy limestone in 

 the upper shale member of the Kiu-lung group [Blackwelder, 19070, 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; also (C55), just below the Ch'au-mi-tien 

 limestone in Ku-shan shales [idem, p. 43], in isolated hills at an elevation of 380 

 feet (114 m.) above the W6n-ho, 12 miles (19 km.) south 80 east of Tsi-nan, Shan- 

 tung, China. 



Collected by Bailey Willis and Eliot Blackwelder. 



Drepanura premesnili Bergeron. 



Plate 10, Figures 2, ?a-d; Plate n, Figures 1-5. 



Drepanura premesnili BERGERON, 1899, Bull. Soc. geol. de France, 3d ser., vol. xxvn, p. 509, plate 13 



fig. 8. (Species described and discussed.) 

 Drepanura premesnili Bergeron, MONKE, 1903, Jahrb. konigl. Preuss. Geol. Landesanstalt und 



Bergakademie, vol. xxni, pt. I, p. 124, plate 5, figs. 5-19; plate 9, No. 4. (Describes and 



discusses species very fully.) 



M. Bergeron founded this genus and species on the pygidia occurring on a 

 thin slab of limestone. Subsequently Doctor Monke described in detail and illus- 

 trated the cephalon, thoracic segments, and pygidia. Among the collections of the 

 Carnegie Institution of Washington Expedition, fine illustrations of the cranidium, 

 free cheeks, and pygidia occur, also fragments of the thoracic segments, but nothing 

 is added except that the true stratigraphic position of the genus and species has 



