80 G. F. MATTHEW ; ILLUSTEATIONS OF 



nine, nearly continuons, raised lines extending along its surface, parallel to the front 

 margin. The large lobe of the hypostome has numerous irregularly anastomosing raised 

 lines, which are rudely parallel to the two posterior sides of the lobe, and are, therefore, 

 reversed along the axial line ; these lines are from two to three times more numerous and 

 closely set than those covering a corresponding space of the anterior fold or doubleur. The 

 posterior lobe of the hypostome is smooth, but the posterior marginal fold is traversed by 

 a number of closely set, distinct, raised lines, parallel to its outer margin. 



The pygidium is smooth on the upper surface, and on the under is marked by anasto- 

 mosing raised lines, that are rudely parallel to the margins of the axial lobe. 



This species is near P. Tesseni (= P. Bohemicus) of Europe, but is sufficiently distinct 

 by the features of the head shield, hypostome and pygidium. It is remarkable for its 

 wide eyelobes. 



Length of the largest complete head-shield obtained, 42 mm. Width, between the 

 sutures, 55 mm. Length of a large hypostome, 36 mm. ; width, 58 mm. Length of pygi- 

 dium, 10 mm. ; width, 7j mm. 



Horizon and Locality. In the fine dark shales of Div. \.d, at Porter's Brook, St. Martin's. 



Paradoxides Micmac, Hartt. (Plate VII. Fig. 18.) 



Acad. Geol., 1868. Fig. p. 65*7. Trans. Eoy. Soc. Can., Vol. II. Sec. iv. p. 101. 



Since my former paper was written, I have met with good examples of the cephalic 

 shield of this species, which may be described as follows : — 



The cephalic shield, 28 by 30 mm., of an immature individual, is a third wider than 

 long between the sutures ; it is also a sixth wider behind than before. The front is 

 obtusely subpyramidal, biit the posterior margin is nearly straight. 



The anterior margin and fold are much as in P. Eteminicns, but the flat area is three 

 times longer on the front than at the suture, and is crossed near the suture by a distinct 

 ridge. 



The glabella is nearly as wide as it is long ; it is somewhat augulated in front, con- 

 tracted behind, and with concave margins behind the front of the eyelobes ; it is widest a 

 little behind the anterior third. The furrows are all distinctly impressed ; the first two go 

 all across, and are directed backward : the first is faintly impressed in the middle third 

 and the second also, for a short space on each side of the axial line. Neither of the two 

 anterior furrows reach the margin of the glabella ; the parts of the third furrow are 

 directed forward, and are separated by about one third of the width of the glabella ; the 

 fourth pair is transverse, and its members are separated from each other by half of the 

 width of the glabella. 



The occipital ring is more than three times longer than wide, and the furrow is strongly 

 impressed only at the outer quarters, the tubercle is about one third from the posterior 

 margin. 



The posterior margin is directed backward on each side of the glabella to the angle of 

 the facial suture, where it terminates in a sharp triangular point. The fold is narrow and 

 weak, but the furrow wide, especially at the extremity. 



The fixed cheek is subtriangular, and is separated from the eyelobe by a distinct, well- 

 rounded furrow. The eyelobe is narrow, rounded and unusually long, its arc being two 



