TRILOBITA—OPISTHOPARIA. 



287 



Trenton and Utica. 

 America. 



XXXV. 



Widely distributed in eastern North 



Bathyuriscus Meek. 



Glabella straight or slightly expanded in front, marked by three 

 or four pairs of glabellar furrows. Eyes elongate. Thorax with 

 seven to nine segments; axis strong; pleura with broad grooves. 

 Pygidium semicircular; axis annulated. Cambric. 



79. B. productus (Hall and Whitfield). (Fig. 1591.) Cambric. 



Fig. 1 591' Bathyuriscus productus, central part of head and pygidium. 

 (After Walcott.) 



Thorax of seven segments; pleural grooves extending only about 

 two thirds the distance out from the axis. Pygidium, in well pre- 

 served specimens, showing about six rings on the axis and four 

 or five grooves on the pleural portion, with broad, smooth margin. 



Middle Cambric of Nevada and Utah. 



80. B. howelli Walcott. (Fig. 1592.) Cambric. 



Glabella expanding in front of second pair of glabellar furrows. 



Fig. 1592. Bathyuriscus howelli, 

 the type specimen, X 2. (After Wal- 

 cott. ) 



Fig. 1593. Bathyuriscus ro- 

 tundatus, a large individual. ( After 

 Walcott. ) 



