162 



Dkitrypa bcalaris. Hall. (Fig. 51.) (6th Ann. Rep't 

 N. V. State Geol., ]>. 60, 1886; Report of 1897. PL XI.) 



Distinguishing Characters. — Straight parallel and rigid 

 branches; ladder-like appearance of carinae and scalae, the 

 former projecting above the latter: very oblique scalae, with 

 their summits nearest the base of the frond. 



Found in the Demissa bed, at Section ."> (rare). 



Fig. 51. Unitrypa scalar in. (a) A fragment of the 

 carinae and scala? ; (/<> an enlargement of t tie summits of 

 the carinae and scala?. showing nodes on the carinae. x-4 : 

 (c) an enlargement showing very thin carinae and scalae. 

 x 4 ; id) an enlargement, showing the under side of the carinae and scalae, x 4 : <-./ i trans- 

 verse sections of different fronds, x X : (gri a transverse section further enlarged, showing 

 the rhomboidal form of the branches, in section at the base, where they are connected by 

 the tranverse dissepiment: the branches are continued upward into' the carina-, which 

 are expanded at the summit, and connected by the transverse " scala?" from Hall. > 



Genus P0LYP0RA. McCoy. 



[Ety. : Polys, many; jwros, pore.] 

 (1845: Carb. Foss. Ireland, p. 206.) 



"Bryozonm having the same manner of growth and 

 genera] aspect as Fenestella, but having the cell apertures 

 disposed in three or more ranges, entirely covering the cel- 

 lnliferous face of the branches, which are without a median 

 keel or carina." (Simpson, Pal. Bryoz., p. 502.) 



Polvpora multiplex. Hall. (Fig. 51A.) ( Rep't State 

 Geol. for 1886, p. 00, ibid. 1887. PI. XL) 



Distinguishing Characters. — Large infundibulif< >rm fronds, 

 with frequent longitudinal folds or undulations. Xon-celln- 

 Hferous face; moderately slender, sharply angular, straight 

 and rigid, or more or less zig-zag branches, with a slight 

 carina : comparatively strong, sharply angular dissepiments, 



