PLATE 61. 
1. 306. 3. Asaphus? nodostriatus. (Pag. 248.) 
1 a. The fragment, natural size. 
1 b. A magnified portion of the surface, showing the lamellose striae, with small nodes which interrupt the 
lines. 
2 . 
303. 4. Ceraurtts? pustulosus. 
(Pag. 246.) 
2 a. The fragment, natural size. 
2 b. A magnified portion of the same 
3, 4. 43. 1. Isotelus GIGAS. (Pag. 231.) 
3 a. The buckler of an individual of medium size. This is more extended in front, and the eyes are more 
prominent than usual. 
3 b. The caudal shield, corresponding in size to the buckler. The crust is removed, showing the lines of the 
articulations. 
3 c. A portion of the surface of the buckler enlarged, showing a peculiar punctate structure which is scarcely 
visible to the naked eye. 
3 d, e. Lateral and dorsal views of a small perfect specimen from Kentucky. The buckler is somewhat com¬ 
pressed or bent in front, so that the facial suture is not shown to its full extent. 
3 f. Buckler of an individual of ordinary size. The eyes are prominent, but less proportionally elevated, and 
the whole less convex than the specimen 3 a. The course of the facial suture is distinctly visible. 
3 g. Caudal shield corresponding in size to the buckler 3 f : the marks of the transverse segments scarcely 
visible. 
3 h. View of the eye of 3 / (natural size), as seen looking forwards and outwards. 
3 i. Oblique front view of the eye, which, under ordinary magnifying glasses, presents no granulations. 
3 k. The labrum or epistoma, showing the inner or upper side. 
3 m. A portion of the same enlarged, showing the striae upon the surface. 
4 a, b, c. Front, lateral, and dorsal views of the original specimen to which Green applies the name of 7. 
cyclops . 
