61 



The following are the systematic descriptious : — 



Class AOTINOZOA. 



Order ZOA^' Til ARIA. 



Section ZoANTHARiA scLERODERMATA (Madreporaria), 



Family Favositid^. 



Genus Favosites, Lamarck (pars.), 1816. 



Favosites grandipora, sp. nov. 

 (PI. viii., Figs. 6-9.) 



Sp. Char. — Corallum generally forming sublobate, ramose 

 masses, but variable in size, apparently dichotomously 

 branched, the whole free surface occupied by the calices of 

 the corallites, the axial portion of the corallum being much iu 

 excess of the peripheral. Corallites long and slender, in the 

 axial region polygonal, but from the deposition of secondary 

 matter, or sclerenchyma, becoming oval or irregular in outline ; 

 usually equal in size, but with smaller angular calices inter- 

 spersed throughout ; the larger are one millimeter in diameter, 

 the tubes gradually curving outwards to the narrow periphery, 

 and then becoming almost horizontally inflected ; opercula 

 not observed. Walls thin, but more or less thickened by a 

 deposit of sclerenchyma. Septa obsolete. Pores very large, 

 regular, round, usually forming a single row in the median 

 line of each face of the corallites. Tabulce simple, complete, 

 as fine hair-like lines, mostly horizontal, but at times a little 

 arched upwards, and seldom oblique. 



Obs. — Favosites grandipora is by far the most representative 

 fossil of the deposit. Its growth was certainly ramose, the 

 largest stem observed being two and a quarter inches in 

 diameter, but this was probably exceeded, as other examples, 

 massive and non-ramose, and corresponding in macroscopic 

 characters to the above, are probably only the interior portions 

 of large stems. 



The remarkable size, regularity, and contiguity of the pores 

 is a very prominent feature. Other uniserial forms of 

 Favosites, as to the position of the pores, are known, but are 

 chiefly Devonian in age, F. turhinata, Billings, F. hamilfonensis, 

 Kominger, F. intella, Winchell, &c. The close serial arrange- 

 ment of these large pores gives rise to a very peculiar 

 appearance in longitudinal sections, when erosion of the 

 corallite wall has just commenced, and sufficient to render 

 the pores partially confluent. The breaking up of the 

 wall thus brought about simulates so many thick incomplete 

 tabulee, after the manner of those of Favosites (Emmonsia) 

 hemispherica, Yandell.* The pores are as conspicuous on the 



* Nicholson, Tab. Corals Pal. Period, 1879, t. 3, f . 36. 



