48 



paLjEontolooy of nbw-yosk. 



428. 3. PH.ENOPORA ENSIFORMIS(r,. SJ3.)- 



PL. XVIir. Fig. 8o, 6, c. 



Stipe ensiform, narrowing and curved towards the base ; surface at the larger extremity 

 marked by eight or nine rows of rhomboidal reticulations, within which the oval openings of 

 the cellules are scarcely discernable : three of the central rows are continued to the smaller 

 extremity of the stipe. 



This species is quite abundant, and, when nearly perfect, is readily distinguished by its form. 

 The openings of the cellule vary little in size from those of the first species described, though 

 they are always rather more conspicuous, and appear more nearly rectangular. The longi- 

 tudinal and transverse decussating lines are very prominent. 



This species is rarely found more than an inch in length, though great numbers often appear 

 upon the same specimen of stone. When the curved portion is broken off, the slightly larger 

 openings, the sharper edges of the decussating lamellae, and the narrow form, will suffice to 

 distinguish it from P. explanata. 



Fig. S a. A single individual of the natural size. 



Fig. 8 J. A portion of the same enlarged. 



Fig. 8 c. A fragment of stone having several specimens upon the surface. 



Position and locality. In the thin layers of siliceous limestone in the lower part of this 

 group, at Flamborough head, Canada West. 



Gekus RHINOPORA {nov. gen.). 

 [Gr. pivrj, lima, and *opos, porus.'\ 



Corallum consisting of an expanded calcareous crust, either subcylindrical and hollow or 

 explanate, poriferous on the two sides ; cells arranged somewhat in quincunx order, roundish 

 or oval, and strongly raised in little papilla; or pustules above the surface. 



429. 1. RHINOPORA VERRUCOSA (?(. 5;?.). 



PL. XIX. Fig. 1 a, 6, c. 



A somewhat thin expanded calcareous crust of irregular form ; surface covered with roundish 

 elevated cells, a little more than their own diameter distant from each other ; openings round 

 or round-oval, directed upwards ; surface between the cells granular. 



Cellules 64 in the length of an inch. 



This species is very abundant, occurring in fragments of greater or less magnitude. It is 

 clearly celluliferous on both sides, the callicles rising so much above the surface as to make it 

 rough like a grater. All the specimens seen are fragments, the original having probably been 



