316 Fi-cderi ch Cliapmnii : 



A(iiioxtu>! rlii lie II ></■■>. Dames.' is another species allied to ours. 

 It was deseriV)ed from the Cambrian beds of the Province of 

 Liau-Tung, China. This species shows the same general charac- 

 ters as ours, but in A. chinensu the lateral lobes of the tail- 

 shield are not so wide, thus agreeing more nearly with Agnnsfus 

 jiisiforniis ; and moreover, the pygidial axis is not so bluntly 

 pointed posteriorly. 



Horizon. — Upper Cambrian, Agnostus Zone, Dolodrook River. 



Genus Pfi/choparia, Corda, 1>^4:7. 



Ptychoparia thielei, sp. nov.^ 



(PI. LVIIT., Figs. 2, 3, 5, 7, and 10). 



Description. — Head-shield large, comparatively bix)ad in front. 

 Glabella large and tumid, elongate and tapering somewhat to- 

 wards the front ; more than two-thirds the ejitire length of 

 head ; surface finely tuberculate, marked by iibout four pairs of 

 lateral furrows, almost or quite continuous. Palpebral lobes 

 sub-lunate, prominent ; eye-lobes very narrow, not conspicuous. 

 Facial sutures strongly curved at the eye-margin, turning at a 

 sharp angle anteriorly, directed forward and outward, and then 

 gently inward to the anterior margin, which it meets a little 

 nearer the central line than the eye ; from the posterior end of 

 each, eye the suture curves gently outwards, then extends 

 horizontally, and finally is directed obliquely to meet the lower 

 border of the strong genal spine. Tlie cephalic border is finely 

 wrinkled and tuberculate ; whilst the prominent areas of the 

 free cheeks are radiately wrinkled. 



Thoracic segments fragmentaiy ; none in position. 



Pygidiuni semicircular, rounded posteriorly ; moderately large, 

 with about eight distinct segments. Surface finely tuberculate. 

 Axial lobe elevated, rounded, extending to the j^osterior border ; 

 width at the anterior region equalling about one-third of the 

 lateral lobes ; the latter depressed or only slightly convex. 



Dimensions. — Width of cephalic shield to bases of spines 

 (approximate), 59 mm. ; length through the central axis, 15.5 



1 In Richthofen's "China," vol. iv., 1883, p. 27, pi. ii., fiys. 18, 19. 



2 Named in honour of its discoverer, Mr. E. O. Thiele, B.Sc, F.G.S. 



