PLATE II. 



AULOPORA SCHOHARIiE. 



Page 3. 

 A specimen, natural size, attached to the surface of Atrypa reticularis. 



Lower Heldei-berg group. ClarksviUe, N. T. 

 A specimen upon a piece of limestone, showing a mode of budding in a more direct line than usual. 



Lower Helderbei-g group. Clarksville, N. Y. 

 Another sijecimen 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 gi'oup. iSchoJiarie, N. Y. 

 An enlargement from tig. 3. 



An enlai'gement 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. 



AULOPOKA TUBULA. 

 Pago 3. 

 Fig. 7. A colony of cells attached to a fossil shell and closely crowded in their mode of growth. 



Lower Helderberg group. Schoharie, N. Y. 

 Fig. 8. A colony of cells which have grown upon the surface of a Strophodonta — less crowded in their 

 mode of growth than in tig. 7. 



Lower Helderberg group. Schoharie, N. Y. 



AULOPOUA SUBTENUI8. 

 Page 4. 

 Fig. 9. 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 Ueklerberg group. ClarksviUe, N. Y. 

 Figs. 10, 11. Two slender specimens, natural size, showing some slight variation in the budding. 



Lower Helderberg grouj). ClarksviUe, N. Y. 

 Figs. 12, 13. Enlargements, to three dianietei-s, of parts of a specimen of this species. 



F^g. 15. 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. 

 Fig. 16. An enlargement from the pi-eceiiing, showing the mode of growth, and the manner of budding in 

 a dii-ect line along the convex side of the tube. The surface shows distinct longitudinal strise 

 with transverse cun-ngations fjiving a papillose surface. 

 Figs. 17, 18. Specimens pi-esitnting the same charactei'S as the preceding, except that the tubes are more 

 direct, leas curved and more slender. 



