131 MEMBRANIPORID^. 



and Purpura) (Busk) : Tertiary beds^ Vienna Basin 



(Reuss)? 



Mr. Busk assigns avicularia to M. monostachys ; but as 

 I liave never met with tliem on any of the specimens from 

 very various localities which I have examined^ I have 

 omitted the character. There are structures, however, 

 scattered over the zoarium, which in some measure 

 remind us of avicularia. These are dwarfed and imper- 

 fectly developed cells, which are interspersed in consider- 

 able numbers amongst the normal zooecia. They are of 

 small size, roundish, or miniature copies in shape of the 

 ordinary cells, with a subcircular or oval aperture, which 

 is covered in by a delicate membrane. 



Membranipora catenularia, Jameson. 



Plate XVII. figs. 1, 1 «, 2. 



TuBiPORA CATENULARIA, Jamcson, Wem. Mem. i, 561. 



TuBiPORA CATENULATA, Stewart, Elem, ii. 425. 



HiPPOTHOA CATENULARIA, FlcM. B. A. 634 : Jolin&ton, Brit. Zooph. (ed. 2), 



i. 291, pi. 1. figs. 9, 10 : Busk, B.M. Cat. i. 29, pi. xviii. 



figs. 1, 2. 

 HiPPOTiiOA Elliot.e, Gray, Zool. Misc. 34. 

 Pyripora RA5I0SA, D'Orb. Pal. Fran9. Terr. Cret. v. 539. 

 ? HiPPOTiiOA RUGOSA, Stimpson, Invert. Grand Manan, 18. 

 Membranipora pilosa, forma caten'ulaiua {M. catenularia), part., Smiff, 



Kritisk Forteckn. iii., ffifvers. K. Vetensk.-Akad. Forhandl. 



1867, 370 and 415, pi. xx. fig. 45. 



Zooecia contiguous, ovate above, more or less produced 

 and narrowed below, linked together in linear series, 

 from which branches are given off irregularly, fre- 

 quently anastomosing, or massed together and coales- 

 cent ; walls solid, smooth, or transversely Mrinkled ; 



