159 



Genus FENESTP]LLA. Miller. 



[Ety. : Fenestella, little window.] 

 (1839: Lonsdale in Murchison's Sil. System, Pt. II., p. 677.) 



Bryozoiini, consisting of ix calcareous branching fron<l, 

 forming cup-shaped or fnnnel-shaped expansions. The 

 branches fork, and are connected by transverse bars or dis- 

 sepiments, thus enclosing spaces or fenestrules. The cell 

 apertures occur on one side of the branches. They are sur- 

 rounded by rims or peristomes, and are arranged in two 

 parallel rows, while between them occurs a ridge (carina), 

 or a row of nodes. 



Fenestella emaciata. Hall. (Fig. 47.) (oGtli Ann. 

 Eep't N. Y. State Mus. Xat. Hist., p. 08, -tlst Rep't, do., PL 

 VHI.) 



Distinguishing Cinirncters. — Large, funnel-sha])ed frond; 

 longitudinal striations of branches on the non-celluliferous 

 face, with thin, ()l)li(pie dissepiments; angular character of 

 branches, and dissepiments on celluliferous face; closely and 

 regularly (lisi)osed cell apertures. 



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



CL 



Fig. 47. Feiu^^iella emdcinfu [tvom HallL hm FraKuieiit of t'l-niid. ri'diiced : i/<) an en- 

 larfjement from the non-eelluliferous face, sliowiiij; the striated ^raiiulnst' hraiiehes. and the 

 obHque dissepiments, 4 x : ic) an enlargement finm tlie eeHuhft-rous I'aee. sli(i\vin}< the form 

 and disposition of the cell apertures, 4 x : id) a transverse section of the branches, 4 x : 

 (e) a lateral view of the branches, showing the dissepiments and position of the apertures. 

 4 X. 



Fenestella planiramosa. Hall. (Fig. 48.) (36th Ann. 

 Rep't N. Y. State Mus. Nat. Hist., p. 02; Rep't State Geol.. 

 1887, PI. I.) 



