NO. 1415. CAMBRIAN FAUNAS OF CHINA— WALCOTT. 77 



increasing in width toward the center, wdiere it is sliohtly convex, and 

 marked at the center by a minute sharp tubercle; dorsal furrow 

 strong- and rather deep about the glabeUa. 



Fixed cheeks about the same width as the o-la])ella, moderately 

 convex; they slope gently from the dorsal furrow to the palpebral 

 lobe, and backward to the furrow of the posterolateral linil); in front 

 thev slope rather rapidly and merge into the frontal limb; palpebral 

 lobes small and situated about their own length from the posterior 

 margin of the head; ocular ridge very faint, scarcely perceptible 

 except by turning the specimen in the light; frontal limb slightly con- 

 vex, sloping gently downward, and divided midway by a longitudinal 

 furrow that extends from the front of the glabella to the furrow within 

 the frontal rim; each side of the longitudinal median furrow the frontal 

 border extends outward and backward, merging into the tixed cheeks 

 without any interruption in the convexity of the slope; frontal rim 

 narrow, nearly tiat, and separated from the frontal limb ))V a very 

 shallow groove which is little more than a change in slope of the 

 frontal limb to the nearly tiat frontal rim; })ostero-lateral limbs ver}^ 

 short. 



Surface niinuteh" granulose under a strong lens, with a few scat- 

 tered larger granules. The largest head of the species in the collec- 

 tion has a length of 4 nun., with a width at the palpebral lobes of 

 nearly 5 mm. 



This species is characterized l)y the longitudinal furrow in front of 

 the glat)ella, which resembles the longitudinal furrow frequently seen 

 in the frontal liml) of the heads of Acpioistui^i. 



FonnatUm and loaility. — Middle Cambrian, Ku San shale forma- 

 tion; 2.5 miles southwest of Yen Chuang, Hsin Tai, Shangtung. China. 



Collected by P^liot Blackwelder, of the Carnegie Institution of 

 Washington Expedition to China. 



PTYCHOPARIA CONSTRICTA, new species. 



The convex central portions of the head, exclusive of the free 

 cheeks, are subquadrilateral in outline; glaljella subcylindrical, nar- 

 rowing slightly toward the front — only faint indications of glabellar 

 furrows; occipital furrow narrow, clearly defined but shallow; occip- 

 ital ring strong, nai'row at the sides and broad at the center; tixed 

 cheeks a))out as broad as the glabella; ocular ridges strong and merg- 

 ing into the rather long palpebral lobes; frontal limb well defined by 

 the ocular ridges and narrow, slightly flattened, frontal rim. 



Surface slightly roughened by minute irregular raised lines. 



Formation und loadity. — Lower Cambrian, Man To formation, 

 lower part of southeast slope of Hu Lu Shan; 2.5 miles south of Yen 

 Chuang, Hsin Tai, Shangtung, China. 



