PLATE II. 
Fig. 1. 
Fig. 2. 
Fig. 3. 
Fig. 4. 
Fig. 5. 
Fig. 6. 
Fig. 7. 
Fig. 8. 
Fig. 9. 
Figs. 10, 
Figs. 12, 
Fig. 15. 
Fig. 16. 
Figs. 17, 
AULOPORA SCHOHARIiE. 
\ i. fl'815'l 
Page 3. 
A specimen, natural size, attached to the surface of Atrypa reticularis. 
Lower Helderberg group. Clarksville, N. Y. 
A specimen upon a piece of limestone, showing a mode of budding in a more direct line than usual. 
Lower Helderberg group. Clarksville, IV. Y. 
Another specimen on the surface of a fragment of limestone, showing a compacty arranged 
colony, the cells diverging and tending to form a reticulate arrangement. 
Lower Helderberg group. Schoharie, N. Y. 
An enlargement from fig. 3. 
An enlargement showing a varying size of cells on the same specimen. 
An enlargement of a specimen, showing a partial abortion of two of the cells, while a third has 
continued to enlarge. 
Aulopora tubula. 
Page 3. 
A colony of cells attached to a fossil shell and closely crowded in their mode of 
Lower Helderberg group. Schoharie, N. Y. 
A colony of cells which have grown upon the surface of a Strophodonta — less 
mode of growth than in fig. 7. 
Lower Helderberg group. Schoharie, N. Y. 
Aulopora subtenuis. 
Page 4. 
A fragment of rock preserving a small colony in which the budding is more directly lateral and 
more distant, and the tubes more slender than in either of the preceding species. 
Lower Helderberg group. Clarksville, N. Y. 
11. Two slender specimens, natural size, showing some slight variation in the budding. 
Lower Helderberg group. Clarksville, IV'. Y. 
13. Enlargements, to three diameters, of parts of a specimen of this species. 
A group of cells of natural size, which are slightly stouter, and enlarging more rapidly than the 
preceding specimens. 
Lower Helderberg group. Schoharie, N. Y. 
An enlargement from the preceding, showing the mode of growth, and the manner of budding in 
a direct line along the convex side of the tube. The surface shows distinct longitudinal stri£e 
with transverse corrugations giving a papillose surface. 
18. Specimens presenting the same characters as the preceding, except that the tubes are more 
direct, less curved and more slender. 
growth. 
crowded in their 
