5-3 A CoXTKlliUTlOX TO TTIE LoWER DeVONIAX FauXAS OF MaRYLAXD 



concave furrow; geiial angles much extended, rectilinear, or slightl)" 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 

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

 are three shorter obtuse projecting i^rocesses 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 al^out half the distance from the axial line to the 

 dorsal furrows; pleurse with about IG 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 

 an-hed slightly forward till near the lateral margins when they bend 

 suddenly backwards. Xo eaudal spine observed. 



Tlie surface of the cephalon is ornamented with numerous irregularly 

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

 each of the transverse ridges several spines more crowded toward the dorsal 

 furrows, but with no regular arrangement observable; the plural ribs 

 studded with pustules varying greatly in size and occupying usually a 

 medial position on the rib. 



The cephala are fragments and are completely separated from their 

 pygidia. Each belongs to a large species. Eelying then on the highly 

 probable conjecture of identity of localities and on the large size of the 

 individuals, the writer has referred the pygidia and the fragmentary 

 cephala to the same species. It must remain for future investigation lo 

 ,show the truth or falsitv of such reference. 



