86 



XORTH AMERICAN INDEX FOSSILS. 



In the Onondaga limestone of New York, Canada, Michigan 

 and the Falls of the Ohio. Also in the Hamilton group of 



Michigan. 



87. F. basalticus Goldfuss. 



(Fig. 



Fig. 139. Favosiles 

 basalticus (enlarged). 



39-) 



Devonic. 



Tubes of medium size, sometimes unequal, 



tabulae complete, not very close together, the 



squamae often not preserved. Generally only 



a single line of mural pores on each wall. 



In the Onondaga limestone of New York, 

 Canada and Northern Ohio. 



88. F. tuberosus Rominger. Devonic. 

 Columns of medium size (2-3 mm.), from two to three rows of 



mural pores on each face, and two rows of stout horizontal squamae 

 on inside of each face; the squamae of adjoining rows alternating 

 and often interlocking. Pores surrounded by small pits. Oper- 

 cula frequent and concave. 



In the Onondaga limestones of western New York, Canada, 

 Michigan and the Falls of the Ohio. 



89. F. epidermatus Rominger. Devonic. 

 Differs from F. tuberosus in irregular arrangement of squamae and 



in elevated ring around the small distant pores in rarely more than 

 two rows. Interior of tubes with twelve longitudinal furrows 

 which are commonly visible in reverse on the outside of solid col- 

 umns. The squamae are on the spaces between the grooves and 

 the tabulae are complete. 



Common in the Onondaga limestone of Western New York, 

 Canada, Michigan, Indiana and Kentucky. 



90. F. emmonsi Rominger. Devonic. 

 Tubes from 1 to \y 2 mm. in diameter. Tabulae for the most part 



very irregular, closely crowded and compound from union with 

 squamae ; pores large, irregular, in from I to 3 rows and often 

 crowded. Differs from F. epidermatus in the crowded incomplete 

 tabulae and in the large crowded pores. 



In the Onondaga limestone of New York, Canada, Michigan, 

 Ohio, Kentucky, etc. 



91. F. turbinatus Billings. Devonic. 

 Form turban-like, often simulating Cyathophylloid corals, i. e., 



cup-like; generally curved in the basal portions and not infre- 

 quently looking like the mold of large pelecypod shell. Coral- 



