161 



Distinguishing- Chnr act ers. — Reticulated aspect of frondvs; 

 oval fenestrnles; nine to ten apertui-es to each fenestrnle, 

 completely surrounding" it. (On account of the expansion of 

 the carina to nearly the middle of the branches, this face 

 may appear like the non-celluliferons face, especiallv ^Yhen 

 embedded in rock. ) 



Found in the Demissa bed, at Section •") (common). 



Genus RETEPORIXA. D'Orbigxy. 



[pyrv. : Btte, net; poras, pore.] 

 (1850: Prodoine de Pal.. T. I., p. 101.) 



Bryozoum fenestelloid, with sinuous and anastomosinii,' 

 branches. The non-celluliferous side has the appearance of 

 a net-work, with oval fenestrnles; while the cellniiferous 

 side shows sinuous branches, with a doultle row of 

 apertures on each. 



Reteporina striata. (Hall.) ( Fio-. .")().) 

 (Gth Ann. Rep't X. Y. State (ieol., p. 4.',. PI. HI. 

 1SS6. ) 



Distinguishing Cii.-i racters. — Reticulated 

 appearance of frond: fre(piently a pi-ominent 

 node at point of junction of branches ; sinuous 

 branches of celluliferous face, apparently con- 

 nected by wide, depressed dissepiments; thin, f"'"- ^^- ^^''- 



•^ ' ' ' pan ltd striaiii. 



elevated and crenulated carina between a]»er- an7 " cHiuiiferous 



-f-111-oa sides. eiilai'Ked. x 



'^^"'^*- 4 (after Hall). 



Found in the Demissa bed, at Section 5. 



Genus UXITRYPA. Hall. 



[Ety. : Unus, one ; try pa, perforation.] 

 ( 1885: Rep't N. Y. State Geologist for 1884, p. 36.) 

 Bryozoum consisting; of fenestelloid fronds, with two 

 rows of apertui-es, separated by a carina on the celluliferous 

 face of each branch. The carina^ ai"e prominent, high, thick- 

 ened near the top, and those of adjacent branches are 

 connected by thin obli(|nely-]ilaced, oi- abrn])tly-l)ent, trans- 

 verse ])lates oi' sciiln'. 



