264 REPORT OF NATIONAL MUSEUM, 1897. 



Tt'st cousistinji; of irregularly heaped cbaraLers 8ul)fan)ily Tixoi'orix.e 



Lenticular or subspba-roidal, with radiatiiiij; marginal 8]iini'8 and tnberculated 

 surface; chambers arranged in tiers on each side of a central ])lanosi)iral disk: 



Genus Tinoporus. 



8pb:eroidal or spreading, without spines; free or adherent, structure acervuline, 



radiating or laminated; chambers rounded or polyhedral, coarsely perforated; 



no general aperture Genus Giipsina. 



i'binocon vex, spreading, adherent; chambers acervuline; wall linely perforated ; 



apertures numerous, marginal Genus Apliroshia. 



G(dumnar, branching, attached by the base; segments numerous, crowded 

 around the long axis; coarsely perforated; no general aperture: 



Genus TItalamopora. 



Encrusting or branching, parasitic; surface arecdated; color ]iink or sometimes 



white (Jenus rohjlremn. 



Family X. Nummulinid/E. 



Bilaterally synnnetrical; chambers extending from end to onA and arranged in con- 

 volutions perpendicular to the long axis of the shell ..Subfamily Fi'suLiNiN/E. 



Fusiform or subglobular ; chambers entire Genus Fusiilina. 



Subglobular, elongated or subcylindrical; chambers subdivided by secondary 



septa CJenus Schnuigenna. 



Bilaterally symmetrical, nautiloid Subfamily Poi^ystomei.lin.e. 



Supplemental skeleton absent or rudiuu-ntary ; no external septal pores or 



bridges ; aperture a curved slit ; (ienus Nonioniiia. 



Supplementary skeleton, septal biidges and canal system present; aperture a 

 V-shaped line of perforations at the base of the septal face.. Genus Folystomclla. 



Lenticular or complanate Subfamily Nummulitin.e. 



Lenticular, consisting of a coiled nonseptate tulio embedded in a mass of shell 



substance Genus Archddisctis. 



Lenticular, spiral, ineiiuilateral; chambers e(]uitaut, simple above, constricted 



into two ])ortions below Genus Amph iufcf/i^a. 



(!om])lanate and planos]>iral, all the convolutions visible; chambers undivided* 



Genus OprrcnUna. 

 Complanate and ])lanos)>iral ; chambers dixided into chamberlets: 



(4 e u u s He tcrosi ei/ i n a . 

 Jjcnticular, planftspiral, e(|uilateral ; chambers c(|uitant, each convolution nearly 



or (juite enclosing all the ])revious ones (ienus u^'^iimmuUtcs. 



Complanate, regular, equitant, but the alar prolongations thin and transparent, 



exposing the outlines of previous convolutions Genus Assilina. 



Complanate with thickened center, or lenticular Subfamily Cycloclypeix.e. 



Composed of a single layer of chambers arranged in concentric annuli, with 

 superimposed lamina; of finely tubulated shell substance thickest at the center: 



Genus CijcJoclypeus. 



Composed of a single layer of concentric (diambers, with superimposed layers of 



llattened chambei lets (xenus Orhitoides. 



CATALOGUE. 



Family II. ASTRORHIZID.I5. 



Test invariably composite, usually of large size and monothalamous; 

 often branched or radiate, sometimes segmented by constriction of the 

 walls, but seldom or never truly se]>tate; polythalamous forms never 

 symmetrical. 



