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Ceraurus pleurexanthemus.
EXPLANATION OF PLATE XI.
Figure A. | Section of thorax at fourth segment; enlarged to two diameters. | |
a. | Axial groove. | |
bb. | Axial processes. | |
cc. | Thoracic pleuræ and triangular depressions. | |
dd. | Circular cavities. | |
ее. | Free pleuræ. | |
gg. | Inner extremities of thoracic pleuræ. | |
Figure B. | Interior of the dorsal shell; enlarged to two diameters. | |
1. | Hypostomatic suture. | |
2. | Hypostoma. | |
3. | "Doublure." | |
4. | Occipital depression. | |
5. | Occipital cavity. | |
6,7. | Facial sutures cutting "doublure." | |
8. | Glabellar depressions and processes. | |
9. | Neck depression. | |
10. | Spines of the head. | |
a. | Axial groove. | |
bb. | Axial processes. | |
cc. | Triangular depressions. | |
dd. | Circular cavities. | |
ее. | Free pleuræ. | |
f. | Crescent shaped surface on free pleuræ. | |
m. | Elevated margin of the hypostoma. | |
rr. | Axial processes. | |
s. | Smooth crescent-shaped surface on "doublure." | |
t. | Pygidium. | |
x. | Oval openings. | |
z. | "Doublure." | |
Figure C. | Longitudinal section at median line; enlarged to two diameters. | |
1. | Hypostomatic suture. | |
2. | Hypostoma. | |
3. | "Doublure." | |
4. | Head. | |
5. | Thorax. | |
6. | Pygidium. | |
Figure D. | Section of segment at median line; enlarged to five diameters. | |
1. | Posterior reflected articular margin. | |
2. | Outer surface of segment. | |
3. | Union of articular fold and axial ring. | |
4. | Articular fold. |