u8 NORTH AMERICAN INDEX FOSSILS. 



III. Vinella Ulrich. 

 Attached to shells, crinoid stems, etc., and consisting of very- 

 slender tubular stolons arranged in more or less distinct radial 

 manner, each marked in perfect specimens by a single row of pores. 

 Zocecia unknown. 



6. V. repens Ulrich. (Fig. 177, c, e.) Ordovicic. 



Radial arrangement imperfect. Stolons often bifurcating. 

 Black River formation of Minnesota. 



IV. Allonema U. and B. 



Attached, in form sausage-like strings of vesicles with minute 

 punctate surfaces and a large pore toward one end. Sil.-Penn. ? 



7 A. fusiforme (Nich. and Eth.). (Fig. 177, d.) Mid-Devonic. 

 Fusiform, sometimes ovate cells, isolated or joining one another. 

 Hamilton of Ontario, Michigan and the Falls of the Ohio. 



Order CYCLOSTOMATA Busk. 



V. Stomatopora Brown. 

 Dichotomously branching colonies of attached subtubular or 



subpyriform zocecia, arranged typically in a linear series ; aper- 

 tures subterminal. Ord.-Dev.; Jur.-Recent. 



8. S. inflate Hall. (Fig. 178, a.) Ordovicic. 

 Pear-shaped cells often forming crowded clusters. 



Trenton and Cincinnati beds of New York, Canada, Minnesota, 

 etc., and in the Cincinnati dome region. 



9. S. delicatula (James). (Fig. 178, b.) Ordovicic. 

 Cells longer and more slender than preceding. 



Stones River to Richmond beds of Ohio, Indiana, Kentucky, 

 Tennessee, Illinois, Iowa and Minnesota. 



VI. Proboscina Audouin. 

 Adhering, of several fused rows of cells, sometimes a sheet-like 

 expansion. Zocecia tubular with subterminal apertures. Ord.- 

 Dev. ? ; Jur.-Recent. 



10. P. frondosa Nicholson. (Fig. 178, c.) Ordovicic. 

 Branches reuniting, with distant zocecial apertures slightly- 

 elevated. 



Lorraine and Richmond beds of Ohio, Indiana, Kentucky, 

 Illinois and Manitoba. 



