30 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxix. 



center; dorsal furrow obscure, and interrupted hy the small lobe at 

 the postero-lateral ang-le of the glabella and l)v the ocular ridge at its 

 antero-lateral angle. 



Fixed cheeks about two-thirds the width of the central portion of 

 the glabella; they rise somewhat rapidly from the dorsal furrow to 

 the palpel)ral lobe, and slope gently back to the posterioi; furrow and 

 in front of the ocular ridge rather rapidly to the furrow within the 

 frontal rim; ocular ridges strong and rather prominent; they origi- 

 nate against the antero-lateral angle of the glabella and extend 

 obliquely backward across the fixed cheek and merge into the rim of 

 the palpebral lobe; palpebral lobe elevated abov^e the fixed cheek, 

 prominent, and about one-third the entire length of the head; a shal- 

 low groove extends from the thick, strong, broad, elevated rim down 

 to the fixed cheek; postero-lateral limb about as long from the dorsal 

 furrow to its extremity as the length of the glabella and occipital ring; 

 a narrow furrow within the sharp posterior margin gives it an almost 

 concave form; frontal border transverse or slightlj^ incurved; it is 

 elevated, rounded, and separated from the front of the glabella by a 

 narrow sharply defined furrow that extends outward and slig'htly 

 forward between the rim and the fixed cheeks; it is nearly flat, broad 

 at the center, narrowing- toward the facial suture. 



The associated free cheek is subrhomboidal in outline, with a narrow 

 rim that is slightly flattened in front, becoming more rounded toward 

 the posterior lateral angle, which has a short, sharp, backward- 

 extending spine; the body of the cheek is slightly convex, rising 

 broadly from the border to the base of the eye lobe; the posterior 

 border is short, being cut a short distance within the postero-lateral 

 angle by the facial suture; facial sutures, cutting the frontal limb, 

 extend directly backward, with a slight outward curve to the eye lobe, 

 around which the}' curve; back of the eye lobe the sutures continue 

 with a slight sigmoid flexure outward and backward, cutting the 

 posterior margin a short distance within the postero-lateral angle. 



The associated pygidium, which is referred to this species, is trans- 

 versely semicircular, with a short, conical, convex axis. The axis 

 is divided by two narrow, shallow, transverse furrows into two ante- 

 rior segments and a terminal segment about as long as the two anterior 

 segments. Pleural lobes depressed, nearly flat for a short distance, 

 and then sloping gently down to a narrow, flattened margin; they are 

 marked by three shallow furrows, which separate a strong, anterior, 

 narrow, elevated rim, two slightly convex segments, and a posterior 

 segment at the end of the axis; the furrows and segments stop at the 

 line of the flattened margin, with the exception of the anterior elevated 

 rim, which continues across the margin, and is extended into a strong- 

 spine that curves outward and backward; the border is narrow, slightly 

 flattened and transverse, but somewhat incurved posteriorly; it has 

 four or more short, broad, backward-extending spines. 



