Maryland Geological Survey 501 



furrow narrower than the first; glabella large, becoming narrower pos- 

 teriorly ; frontal lobe depressed, broadly elliptical transversely, surrounded 

 by a broad, shallow furrow except at the posterior extremity; first lateral 

 lobe much larger than the others, subtriangular; second lobe smaller than 

 the first and larger than the third; third lobe narrow, having about the 

 same width as the occipital ring ; first and second lobes almost coalesced 

 towards their outward extremities, a slight tendency towards coalescence 

 likewise observable between the second and third lobes ; second and third 

 lobes extending obliquely inward and forward, the former being more 

 oblique than the latter and both suddenly excavate at their inner ex- 

 tremities; eyes large, elevated, bounded (at least exteriorly) by a broad, 

 concave furrow; genal angles much extended, rectilinear, or slightly con- 

 cave outwardly, till near the posterior extremity where they bend notice- 

 ably inward; neck furrows wide and deep; hypostoma with highly de- 

 veloped ornamentation, the anterior extremity possessing a process 

 which bifurcates a short distance beyond the general outline of the 

 hypostoma, each branch extending arcuately outward and forward (25 

 mm. in the specimen figured) ; on either side of this bifurcating process 

 are three shorter obtuse projecting processes each in succession being more 

 and more subdued. Thorax not seen. 



Pygidium convex, greatly depressed, outline broadly triangular, the 

 lateral margins gently convex outwards; axis broad, depressed, tapering 

 gradually to a rounded apex posteriorly ; dorsal furrows broad, deep, in- 

 terrupted by the transverse furrows except posteriorly, and making with 

 each other an angle of about 20° ; axis with 19 transverse, broad, sub- 

 rectilinear ridges, the intervening furrows being broad and shallow axially, 

 but suddenly deeper at about half the distance from the axial line to the 

 dorsal furrows ; pleurae with about 16 transverse tips, the 8 or 9 anterior of 

 which are divided by a well-marked, broad, longitudinal groove, the re- 

 maining posterior ones being more or less acute ; the transverse ribs are 

 arched slightly forward till near the lateral margins when they bend 

 suddenly backwards. No caudal spine observed. 



The surface of the cephalon is ornamented with numerous irregularly 

 placed, rather small pustules. The axial portion of the pygidium bears on 



