RHIZOPODA. 163 



No. 507. Fusulina cylindrica, Fischer. 

 Sub-Carboniferous, Greenwood Co. , Kansas. 



No. 508. Nummulites nummularia, Brug. 



Tlie genus derives its name from the Latin for " coin." The " Nummulitic 

 Limestone " is a distinct formation of great thickness, in some places several 

 thousand feet, which stretches from France to China. The great pyramids 

 are built of this rock. An example is seen in the plinth or base of Cleopatra's 

 Needle in Central Park, New York. Eocene, Great Pyramid, Egypt. 



No. 509. Nummulites striata, d'Orb. 

 Eocene, Conizac near Alet, France. 



No. 510. Orbitolites. 

 Chalk, Gravesend, England. 



No. 511. Infusorial Earth. 



"About one hundred species of Diatoms have been described by Ehren- 

 berg and Bailey from this earth, beside a few Polycystines (siliceous Foramini- 

 fers) and many sponge spicules." Miocene, Richmond, Va. 



ENLARGED MODELS. 



The following twenty specimens are models, very greatly enlarged from the 

 originals, most of the latter being too small for examination without the aid 

 of a microscope. 



No. 512. [966] Amphistegina vulgaris, d'Orb. 

 Miocene: Bordeaux, France. 



No. 513. [999] Cassidulina serrata. 

 Miocene: Austria. 



No. 514. [1002] Clavulina communis, d'Orb. 



Pliocene: Nussdorf, Austria. 



No. 515. [1059] Cristellaria cassis, Ficht. 

 (Young). Pliocene: Sienna, Italy. 



No. 516. [968] Fusulina cylindrica, Fischer. 

 Carboniferous: Russia, Belgium, Ohio, Nebraska, Kansas, «fec. 



No. 517. [1007] G-lobigerina bulloides, d'Orb. 

 Miocene: Austria. Pliocene: Italy. Living: Adriatic. 



