72 FORAMINIFERA OF THE CRAG. 
either m a recent or fossil state. We have it from various Liassic marls, and it occurs 
in many Tertiary deposits in company with other commoner varieties of the same type. 
In a living condition it is very sparingly distributed. 
Mr. 8. Wood found it in the Crag of Sutton, but the specimens were few and small. 
Subgenus—CristELLaRia, Lamarck. 
Naurinus, Linné, Gmelin, Walker and Jacob, Montagu, Maton and Rackett, Pennant, 
Fichtel and Moll, Sowerby, Turton, Fleming, Brown, &c. 
Lenticuiites, Lamarck, Defrance, Nilsson, Hisinger. 
Lenticuuina, Lamarck, Defrance, Parkinson, &c. 
PotystTomELLa, Lamarck. 
Nummutarta (in part), Sowerby. 
CrIsTELLARIA, Lamarck, Defrance, D’Orbigny, Ehrenberg, Czjzek, Reuss, Minster 
and Roemer, Cornuel, Philippi, Hagenow, Bronn, Morris, Parker 
and Jones, Williamson, Bornemann, Terquem, Carpenter, Costa, 
Seguenza, Brady, Karrer, &c. 
NumMuvttina (in part), D’ Orbigny. 
PHonemus, PHaramum, ANnTENOR, RosuLus, Patrocies, SPHINCTERULUS, CLIsT- 
pHontes, Herton, RutNocurus, Macropitres, Lampas, Scortrmus, ASTACOLUs, 
PerreLes, Montfort. 
Oruas, Montfort, Blainville. 
Lintuvris, Montfort, Blainville. 
SaRacENARIA, Defrance, D’ Orbigny. 
Rosviina, D' Orbigny, Minster and Roemer, Ehrenberg, Czjzek, Reuss, Bronn, Morris, 
Bornemann, Terquem, Costa, Karrer, Stache, &c. 
HEMICRISTELLARIA, HEMIROBULINA, Stache. 
Characters.—Shell round, oval, or oblong, disco-spiral, lenticular, or compressed, bi- 
laterally symmetrical as regards the longer axis, as is the case with the other Nodosarine ; 
formed of a spiral set of chambers, in one or more whorls ; chambers either curved or 
triangular, or both, and variable in size and shape, compactly set, increasing successively 
in size, slowly or rapidly, and more or less embracing the earlier part of the spire. 
Aperture excentric, either slit-like, triangular, or round, radiated, usually close to the outer 
or convex margin, but sometimes pouting and nearer the middle of the septal plane. 
Surface either smooth or ornamented with any or all of the following features— 
limbation of the septal lines, ribs, bars, or granules, umbonal knobs, marginal keel and 
spikes. 
The lenticular Cristellaria without any keel is C. rotulata, Lamarck ; with a keel, 
C. cultrata, Montfort ; with a broad keel, commonly toothed, it becomes C. calcar, Linné, 
When much compressed and broadly keeled, it is C. cassis, F. and M. Some lenticular 
