148 RESEARCH IN CHINA. 



Since the publication of this genus I received Dr. Monke's paper on Cambrian 

 fossils in Shan-tung, in which he describes and illustrates, under the generic name 

 Tcinistion [1903, p. 117, plate 4, figs, i-i i], a trilobite that at first sight appears to 

 be generically identical with Shantmigia. The large palpebral lobes, narrow postero- 

 lateral limbs, broad free cheeks, and conical glabella are much alike in both genera. 

 The frontal limb of Shantungia with the nasute extension of the frontal border is, 

 however, quite unlike the incurved, thin frontal margin of Teinistion [plate 9]. 



Shantungia spinifera Walcott. 

 Plate ii, Figures 9, 10; Plate 14, Figures 6, 6a-e. 



Shantungia spinifera WALCOTT, 1905, Proc. U. S. Nat. Mus., vol. xxix, p. 87. (Described as a new 

 species essentially as below.) 



Cephalon, exclusive of free cheeks and frontal spine, subrhomboidal in outline, 

 moderately convex. Glabella truncato-conical, slightly longer that its width at the 

 base ; at the postero-lateral angle of the glabella a small, low lobe extends out into 

 and partly fills up the dorsal furrow; there is also a slight pit in the dorsal furrow, 

 opposite a point where a second glabellar furrow usually occurs in similar glabella? ; 

 occipital furrow narrow, distinctly defined at the sides but very shallow near the 

 center; occipital ring slightly convex, strong, and of equal width from side to side; 

 dorsal furrow deep at the sides and scarcely perceptible in front of the glabella. 



Fixed cheeks about two-thirds as wide as the glabella ; they rise abruptly from 

 the deep dorsal furrow and then slope upward to the palpebral lobe; back of the 

 palpebral lobe they drop somewhat abruptly to the postero-lateral limb, and in 

 front to the furrow between the frontal limb and rim; palpebral ridge very slight, 

 scarcely perceptible in most specimens; palpebral lobe large, rounded, and rising at 

 the margins above the level of the fixed cheeks; rim of the broad, marginal border 

 with an inward slope toward the fixed cheeks, but not very well-defined furrow such 

 as usually occurs on the palpebral lobes ; the length of the palpebral lobe is about one- 

 half of the distance between the furrow in front of the frontal limb and the posterior 

 margin of the cephalon ; postero-lateral limb slender, and extending more than the 

 width of the glabella outward from the dorsal furrow; frontal limb very short and 

 scarcely separable from the downward slope of the front of the glabella ; at the sides 

 it merges into the fixed cheeks; it is separated from the frontal rim by a peculiar 

 transverse furrow; the latter is formed of two slightly forward-arching, narrow fur- 

 rows in front of the fixed cheeks, that merge into a very shallow furrow in front of 

 the glabella ; the central portion of the furrow arches slightly backward ; the furrows 

 are deepest opposite the antero-lateral angles of the glabella; frontal rim subtri- 

 angular in outline, nearly flat, and extending forward at the center to form the base 

 of a long, slender, rounded spine. 



Surface minutely punctate under a strong lens. 



A cephalon 7 mm. in length, exclusive of the frontal spine, has a width of 9 mm. 

 at the outer margin of the palpebral lobes; the glabella is 2.5 mm. at the base, and, 

 with the occipital ring, is 5 mm. in length ; the flat frontal rim and spine of a ceph- 

 alon of about the same size have a length of about 8 mm., the spine, at the point 

 where broken off, having a width of i mm. 



I do not know of any other form closely related to this species. P roam pyx 

 acuminatum Angelin [(1854) 1878, p. 26, plate 18, fig. 7] has a similar nasute projec- 

 tion on the frontal rim, but it differs in the form of the glabella and palpebral lobes 

 and other details of the cephalon. The same is true of the species described as 

 Ptychoparia f pernasutus Walcott [18840, p. 49, plate 10, fig. 8]. 



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 



