ing directly from the cephalic shield in front of the glabella, and 

 in this respect resembles Homalonotus rhinotropis of Angclin, a 

 species which has been referred by Salter, in his Monograph of 

 British Trilobites, to IT. Knightii. Salter says " the front 

 Fi?- 1- margin is of most singular structure and 



may be described as tricuspid. The nar- 

 row edge is so deeply indented, and at 

 the same time folded, that the front por- 

 tion overhangs the rostral shield, forms 

 i 'ai„„.cne ro.,rn,a Vogdes The 0^6 projectiug auglc flaukcd by two smaller 

 fl:i'^S^^^'^'^'W^^^^^ opposite the axial furrows, ex- 

 actly like the salient and re-entering angles of a fortification." 

 Our species has only the central triangular projection, the mar- 

 gins of which are deflected, and the marginal border unites and 

 forms a triangular projection, directly in front and on the median 

 line. 



The following characteristics are drawn from three specimens, 

 consisting of the glabella and fixed cheeks, and many pygidia 

 found associated with them at the same locality. 



The glabella is convex and widens out posteriorly, being con- 

 tracted in front ; the sides arc marked with three lobes, the 

 basal one large, the middle lobe nearly spherical, the third is 

 somewhat obscurely defined. The fixed cheeks are separated 

 from the glabella by deep dorsal furrows, but opposite the eyes 

 the furrows are restricted by a buttress thrown across it, nearly 

 touching the middle side lobes ; the cheeks are gibbous but not 

 elevated above the glabella, they are narrow along the sides of 

 the glabella and widen out laterally from the eyes. The facial 

 sutures cut the posterior angles of the head, but anteriorly from 

 the eyes these lines run almost straight with a slight tendency 

 outward, and pass over the margin. The neck furrow is con- 

 tinued nearly to the posterior anirles of the head. The frontal 

 limb is triangular in outline, and prolonged into a prominent 

 projection, the bourrelet of the limb is defined by a triangular 

 ridge which forms the base of the projection. The projection is 

 formed by the thickening of the crust and by the union of the 

 outer marginal borders along the median line, it is pointed and 



