226 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 64 



Pygidium large ; axial lobe distinct and narrowing from the 

 front margin to within a short distance of the posterior margin ; it is 

 divided into six rings and a short terminal section by narrow trans- 

 verse furrows ; on the broad pleural lobes seven anchylosed pleural 

 segments similar in appearance to those of the thorax extend from 

 the axial lobe across to the outer rim. 



Surface apparently finely and minutely granular or pustulose. 



Dimensions. — The largest dorsal shield has a length of 24 mm. 



Genotype. — Hanburia gloriosa Walcott. 



Stratigraphic range. — Middle Cambrian : Burgess shale member 

 of Stephen formation. 



Geographic distribution. — Limited to fossil bed on ridge between 

 Mounts Wapta and Field, west of the Continental Divide, British 

 Columbia, Canada. 



Observations. — The existence of free cheeks and facial sutures is 

 problematical, owing to the compression of the thin test along the 

 edge of the cephalon. They seem to be indicated and to form a 

 part of the margin opposite the anterior third of the glabella. There 

 is also a slight line that may be traced diagonally backward across 

 the inner portion of the fixed cheek from about opposite the anterior 

 edge of the middle lobe or tubercle of the glabella. This is sugges- 

 tive of the false " eye line " of Conocoryphe. As I expect to work 

 the Burgess Pass fossil quarry another season, it may be that a more 

 perfect cephalon will be found of this species. The large pygidium 

 and few thoracic segments suggest the order Opisthoparia and 

 family Asaphidse rather than the order Proparia. 



HANBURIA GLORIOSA, new species 



Plate 36, figs. 3, 4 



The generic description includes what is known of this species. 

 Three specimens have been found during the five seasons' collecting 

 at the fossil quarry. These are all compressed in the fine shale, and, 

 like Bnrlingia hcctori^ from the same general horizon on Mount 

 Stephen, had a very delicate test. 



Formation and locality. — Middle Cambrian: (35k) Burgess shale 

 member of the Stephen formation, on the west slope of the ridge 

 between Mount Field and Mount Wapta, i mile (1.6 km.) northeast 

 of Burgess Pass, above Field, British Columbia, Canada. 



Smithsonian Misc. Coll., Vol. 53, 1908, p. 15. pi. i. fig. 8. 



