382 SMITHSOXIAX MISCELLANEOUS COLLECTIONS VOL. 64 



limb and anteriorly into the broad frontal limb ; palpebral lobe of 

 medium size and located just back of the transverse center of the 

 cranidium. Very slight traces of palpebral ridges crossing the fixed 

 cheeks. The facial sutures cut the posterior margin within the genal 

 angles and extend obliquely inward to the posterior end of the eye 

 lobe, in front of the latter they extend gently outward and incurve 

 across the frontal border. Free cheeks about one-fourth the width 

 of the cephalon ; they rise rather rapidly to the base of the narrow 

 eye lobe and may or may not terminate in a genal spine. 



Thorax with from 7 to 1 1 segments ; pleurae with strong longi- 

 tudinal furrow, and usually short falcate ends. The axial portion of 

 the segment may be smooth or have a central node or small spine. 



Pygidium relatively large and with a strong convex axial lobe that 

 is divided into several transverse rings by narrow furrows that are 

 slightly indicated on the pleural lobes by shallow furrows ; border 

 usually broad and slightly flattened. 



Surface smooth or marked by shallow pits, and rarely it is granu- 

 lated. 



Genotype. — Asaphiscus wheeleri Meek. 



Stratigraphic range. — Middle Cambrian to Upper Cambrian. 



Geographic distribution. — The genus is represented by nine species 

 in the Cordilleran area of Montana, Wyoming, and Utah ; two doubt- 

 ful species in the Appalachian area of Pennsylvania, and one species 

 in Manchuria, China. It may be represented in Europe, but in the 

 preliminary study I have not recognized it. 



Observations. — The cranidium of Asaphiscus differs from that of 

 Anomocare in its shorter, smaller eyes and elongate glabella with 

 well-defined lateral furrows and in form of frontal limb and border. 

 The pygidium of the genotype Asaphiscus wheeleri differs from that 

 of the genotype Anomocare Iccvc Angelin in having a much longer 

 axial lobe and narrower border, but these characters may be variable 

 in species referred to either genus. 



Anomocarella differs from Asaphiscus in its shorter, smaller eyes, 

 shorter and broader glabella in proportion to its width at the base, 

 and in its smaller pygidium which has a narrow border. 



The cranidium of Asaphiscus is not unHke that of Liostracus, but 

 the other parts of the dorsal shield differ greatly. Asaphiscus has 

 characters that relate it closely to Ptychoparia. The cranidium has 

 the same form of glabella, fixed cheeks and palpebral lobes. The 

 pleural furrows do not start away from beside the axial lobe as 

 abruptly as in the genotype of Ptychoparia, P. striata, but in other 



