PLATE 66. 
Fig. 1. 
301. 2. Ceraurus pleurexanthemus. 
(Pag. 242.) 
1 a. A fragment of a large individual, preserving the buckler and eight articulations of the thorax. The sur¬ 
face is beautifully and evenly granulated or papillose, with larger tubercles upon the cephalic shield, 
and mamillary tubercles upon the articulations : these are enlarged in the figures 1 b, c, d. 
1 e. Front view of the specimen 1 a, showing the elevation of the oculiferous tubercles. 
1 f. One of these tubercles magnified. When magnified to this degree, they exhibit only rounded granulations. 
1 g. The cephalic shield represented in 1 a, showing the separation of the maxillae y y at the facial sutures. 
1 h. The right maxilla, separated from the cephalic shield. (This figure on the plate is without a number.) 
Fig. 2. 
297. 2. Caeymene beckii. 
(Pag. 250.) 
2 a. An entire specimen, with the exception of the maxillary shields, which are separated at the facial suture, 
leaving the cephalic shield in the usual form. 
2 b. An imperfect specimen, with the maxillary portions partially preserved, but separated at the suture, and 
pressed downwards. 
2 c. The thorax and caudal shield, preserving the crust, with the tubercles upon the middle lobe, in a very 
perfect manner. 
2 d. The cephalic shield, with the maxillary portions separated at the facial suture. 
2 e. The cephalic shield entire, but so much compressed that the eyes are obliterated. The posterior angles 
are too much rounded in the figure; in other respects, the true form of the buckler is represented. 
2/'. The cephalic shield preserved in compact calcareous stone. 
2 g. A larger specimen, in compact limestone, preserving a more convex form in all its parts. 
2 h. A small individual, preserving the thorax and the maxillary portions of the buckler, the glabella being 
separated. 
2 i. The maxillary shields, as they frequently occur in the slate, separated from any other part of the fossil. 
The lower figure is the labrum. 
2 k. A. single maxillary shield of this species. 
Fig. 3. 308. 4. Calymene (Species undetermined). (Pag. 253.) 
3 a. A part of the thorax, preserving eight or nine articulations. 
3 b. The caudal shield, with a few segments of the thorax. 
Fig. 4. 309. 5. Asaphus? latimarginata. (Pag- 253.) 
4 a. The caudal shield of a small individual. 
4 b. A fragment of the lateral lobe of the caudal shield of a larger individual. 
Fig. 5. 
43. 1. IsOTELUS GIGAS. 
The labrum or epistoma of a very large individual. 
(Pag. 254.) 
