ORDER II RADIOLARIA a7 

Carboniferous 
Cretaceous 
Miocene 
Pliocene 
Recent 
Devonian 
Oligocene 
ocene 
Triassic 
EK 


A. Chitinosa Heth |. 0 © Pa | eee sa | 
B. Agglutinantia | | 

Astrorhizidae —— _- = = === - 

Lituolidae i... eae lee Alma Ea ale 
Orbitulinidae Ne eee fee 
C. Porcellanea 
Nubecularidae 


; l l ] 
Peneroplidae ak |e I} | 
Miliolidae Piet | se fi | | 
D. Vitro-Calcarea | | 




Lagenidae 


Textularidae SSS pS id ane ee | 
| | | 
Globigerinidae Racers ETE Lids 

Rotalidae ——/ eee ee ee 


a: | | fl | 
Fusulinidae  — | ...... | : peer sees: | ae | eee \eereeaisee eh ee ti aes ae 
| 
Nummulinidae |... eel RIE a aee | —__ a - 



Order 2. RADIOLARIA. Miiller.! 
(Polycystina, Ehrenberg.) 
Marine Rhizopoda enutting fine, filiform, radially directed pseudopodia, with 
central capsule and extra-capsulum, and usually with delicate silicious skeleton. 
The sarcode body of the Radiolarians is differentiated into (1) an inner 
central sphere or capsule of tough slimy protoplasm containing one or more 
nuclei, vacuoles, alveoles, granules, oil-globules, and sometimes crystals, and 
surrounded by a capsule-membrane perforated by pores or pylae; and (2) an 
outer jelly-like extra-capsulum, the sarcode of which emits pseudopodia. The 
individuals lead usually an isolated existence, and are only rarely united in 
colonies. 
Most Radiolarians secrete skeletons composed either of bars or spicules of 
acanthine (an organic substance allied to horn or chitin) or silica, or they build 
an exceedingly delicate lattice-work composed of transparent amorphous silica. 
Only the latter forms are known in a fossil state, and owing to their minute 
size, are commonly indiscernible except with the aid of the microscope. 
1 Ehrenberg, C. G., Mikrogeologie, 1854, and Abhandlg. Berliner Akad. 1875 (Radiolaria from 
Barbados).—Haeckel, E., Die Radiolarien. Monograph 1862, and Report on the Radiolaria col- 
lected by H.M.S. Challenger, 1887.—Hertwig, R., Der Organismus der Radiolarien, 1879.— 
Stéhr, E., Palaeontographica, XX VI. 1878 (Radiolaria from Sicily).—Riist, D., Palaeontographica, 
XXXI. 1885, XXXIV. 1888, and XXXVIII. 1892.—Dreyer, F., Die Tripoli von Caltanisetta. 
Jenaische Zeitschrift f. Naturw. XXIV. 1890.—Cayeux, L., Bull. Geol. Soc. France, 1894, p. 197. 
