174 BULLETIN 106, UNITED STATES NATIONAL MUSEUM. 



GENERA OF MEMBRANIPORAE UNREPRESENTED. 



For the sake of completeness, definition?- and illustrations of the remaining 

 genera of this group are introduced below, even though fossil representatives of 

 them have not yet been found in the American Tertiary. 



A. Cauloramphus 



C. Membrostega 



D. Antropora 



Fui. 41. Miscellaneous siem-rii of Membraniporae. 



A. Caitlriraniiiliits siihilfi r Norman. 1903. X 25. Recent. 



B. Fon'olaria clliptica Busk, 18S4, X 25. Recent. 



('. Mi-niln-ofstef/a fero.r Kirkpatrick. 1800, X Mn. Recent. 

 D. Aiitniiini-ii iii-uniiUfcni Hineks, 1S80, X 30. Recent. 



Genus CAULORAMPHUS Norman, 1903. 



1903. Cauhii-aiiiii/iux NOKMAX. Natural History of East Finraark, Annals and Magazine 

 Natural History, ser. ~, vol. 11, p. 587. 



Fin. 41'. (icnus Ciiulvi-iiiiiiiliiis Norman. 1903. 



A-C. riniliiKiiii/iJiiix xiihiifri- .lolinston. 1832. A. Zooncia. X 25, showing the stout spines. 

 B. Three views of tin- pedunculate avicularia. I A. H after Hindis. 1S80.) C. Sketch showing 

 dietellae. (After Norman, 19o::. i 



Front wall entirely membranous, the eal<-are<ni> Imrder bearing spines. Avic- 

 ularia talked and situated among the spine- on the Literal margin of the zooecinni : 

 ovicell. when present, very shallow and inconspicuous. Dietellae in 1 the type. 



