MILIOLA.. MOLLUSCA. 21 



Gen. 21. MILIOLA, Lam. 



Shell transverse, ovato-globose or elongated, multilocular, with 

 transverse cells surrounding the axis and alternately covering 

 each other ; aperture very small, situated at the base of the 

 last turn, orbicular or oblong. 



The Miliolites are extremely small multilocular shells, of the size of a millet seed, 

 and are found fossil in quantities so large as to form a great portion of the rocks of 

 certain quarries near Paris. M. Lamarck has, however, procured recent individuals 

 gathered on fuci near the Island of Corsica. 



FAMILY V. CRISTACEA. 

 Shell semidiscoid, with the spire eccentric. 



Gen. 22. ORBICULINA, Lam. 



Shell subdiscoid, multilocular, with compound contiguous turns; 

 spire eccentric ; cells short, very numerous ; septa imperfo- 

 rate. (Fossil.) 



Gen. 23. CKISTELLARIA, Lam. 



Shell semidiscoid, multilocular ; the cells contiguous, simple, en- 

 larging progressively ; spire eccentric, sublateral ; septa im- 

 perforate. 



The Cristellariae are very minute flattened and crested shells, found both fossil 

 and recent. Such as are known have only been described and figured by Fichtel, 

 in his Testacea Microscopica. Vienna, 1803. 



Gen. 24. RENULINA, Lam. 



Shell reniform, flattened, sulcate, multilocular, with linear con- 

 tiguous turns, curved round a marginal axis, the most dis- 

 tant from the axis being the longest. (Fossil.) 



FAMILY VI. LITUOLACEA, 

 Shell partially spiral ; the last turn continued in a straight line. 



Gen. 25. LITUOLA. 



Shell multilocular, partly spiral and disciform ; turns contigu- 

 ous, the last terminating in a straight line ; cells irregular ; 

 septa transverse and simple, the last perforated by from three 

 to six holes. (Fossil.) 



Gen. 26. SPIROLINA, Lam. 



Shell multilocular, partially spiral and disciform, with contigu- 

 ous turns, the last ending in a straight line ; septa trans- 

 verse, perforated by a tube. (Fossil.) 



Gen. 27. SPIRULA, Lam. Nautilus, Lin. 

 Shell cylindrical, thin, transparent, flat, multilocular, partly spi- 

 ral, with the turns distant, the last straight at the end ; trans^ 

 verse septa equally distant, concave externally, with an in- 

 terrupted lateral syphon ; aperture round. 



