FOSSILS OF THE CAMBRIAN. 4} 
transverse furrow that unites them; occipital ring of medium width and 
separated from the glabella by a well-defined, but not deeply impressed 
occipital furrow; dorsal furrows of medium strength on the sides of the 
glabella but scarcely shown in front; fixed cheeks unusually narrow and 
rising directly up to the large, elongate palpebral lobes; anteriorly they 
slope into the groove of the frontal limb; posterior extension and postero- 
lateral limbs unknown; frontal limb between the glabella and furrow nearly 
obsolete, extending beyond the furrow as a broad subspatulate, somewhat 
convex margin. ‘The facial suture curves a little outward in front of the 
eye as far as the furrow of the frontal limb and then recurves inward around 
to the front; after curving around the large eyelobe to near the posterior 
margin, its further course has not been traced. 
Surface smooth or slightly punctate. 
Thorax and pygidium unknown. 
Formation and localities —Cambrian. Prospect Mountain Group, central 
portion Secret Canon shale in New York Canon, and upper layers of same 
on north side’ of the cafton opposite the dump of the shaft of the Richmond 
mine, Ruby Hill, Eureka District, Nevada. 
Dicellocephalus Richmondensis, n, sp. 
Plate x, fig. 7. 
Glabella and fixed cheeks, united, quadrangular in form, the width 
being a little greater than the length. Glabella elongate-subquadrangular, 
lateral margins slightly converging anteriorly, and with the front a little 
rounded; length and breadth as three to four; surface moderately convex, 
and marked by a slightly impressed ‘posterior pair of furrows, directed 
obliquely inward two-thirds the distance to the median line, and two pairs 
anterior to these that are just discernible upon the smooth surface; occip- 
ital ring of medium width, distinct; occipital furrow distinct, but not deeply 
impressed; dorsal furrows well defined at the sides but only a line in front 
of the glabetia; fixed cheeks broad, rising slightly from the dorsal furrows 
to the palpebral lobes and sloping away before and behind quite rapidly; 
frontal limb rather long and wide, the marginal rim broadly arcuate, the- 
