62 TABULATE CORALS. 



doubt. There is also the same general disposition of the cal- 

 ices, there beino;- a marked difference in size between different 

 coralHtes. In this respect, however, the condition of matters 

 resembles that which obtains in lai'ge-sized colonies of the 

 normal F. Forbesi from the Upper Silurian. That is to say, 

 there is an approach to a general equality in size of the tubes, 

 the larger ones not being exceptionally large (mostly from 

 three-quarters of a line to a line in diameter), and being very 

 numerous as compared with the small tubes (PI. III., fig. i a). 

 The distinguishing peculiarity of this form, however, is the 

 quite unusual development of the septa, which are conspicuously 

 visible even to the unassisted eye, and extend a considerable 

 distance into the cavity of the tubes (PI. II., fig. 3). In long 

 sections (PI. III., fig. i b), the septa are seen to have the form 

 of strong spines, with a broad base, and with a distinct upward 

 inclination. The tabulse resemble those of the normal form of 

 F. Forbesi. The mural pores, as revealed by thin vertical 

 sections, appear to be numerous and close-set, being apparently 

 in two or even in three rows ; but I do not think that much 

 stress can be laid upon this character, especially when only 

 known by the, in this respect, partial and imperfect evidence 

 afforded by transparent longitudinal slices. 



Favosites Forbesi, E. and H., var. Tuberosa, Rom. 



(PI. III., figs. 2-2 ^.) 



Favosites hasaltica (pars), Goldfuss, Petref. Germ., PI. XXVI., fig. 4 a (caet. 

 exclusis), 1829. 

 „ hasaltica (pars), Billings, Canad. Journ., new ser., vol. iv. p. 106, 



1859. 

 „ Forbesi, Nicholson, Report on the Palaeontology of Ontario, p. 48, 



PI. VII., fig. 8, and PI. VIII., fig. 4, 1874. 

 • „ iuberosus, Rominger, Fossil Corals of Michigan, p. 30, PI. IX., figs. 



I and 2, 1876. 



Corallum forming cylindrical or club-shaped, rarely hemi- 

 spherical masses, varying from an inch up to half a foot or 

 more in length, according to their age. Corallites conspicu- 

 ously unequal in size, the larger ones being somewhat cylin- 



