VI. -DESCRIPTION OF THE PLATES. 



PLATE I. 



Fig. 1. The body of Syringospharia verrucosa, Duncan. Natural size. 



2. A portion of the surface of the same specimen magnified to show the superficial projections, 



pores, and tubulation. 



3. The top of a large eminence, with pores on its sides ; the tubes are seen crowding the 



surface, and many round markings at the apex denote the openings of internal tubes. 



The specimen is the same as the last, and is more highly magnified. 

 4. The body of Syringospharia monticularia, Duncan. Natural size. 



5. The same specimen magnified in part to show the monticules, pores and openings of 



tubes, with many ramifying and superficial tubes on the surface. 

 6. A monticule more highly magnified to show canal openings, canals and spaces between 



them, also some small monticules. 



7. The body of a smaller and less mature specimen of Syringospharia monticularia. 



8. A portion magnified, the radiating canals and the canal openings being shown on the 



monticules. 

 9. A portion more highly magnified, showing a large monticule and smaller ones, with 



superficial tubulation and the exit of internal tubes. Pores are also shown. 



10. A part of the body of a large specimen of a mature Syringosphferia monticularia. 



11. A portion considerably magnified, showing a minute monticule and two pores. The 



tubulation is between the dark lines, and the dots on the monticule and elsewhere are 

 the openings of internal radiating tubes. 



1 2. A portion less highly magnified, showing numerous minute pores and larger monticules. 



