140 THE PROTOZOA 



or sexual. Genera: Gonium O. F. Miiller (1773); Stephanosphcera Cohn 

 ('53); Pandorina Bory de St. Vincent ('24); Eudorina Ehr. ('31); Volvox 

 Leeuw. Ehr. ('38) ; Pl&odortna Shaw ('94) ; Platy donna Kofoid ('99). 



Order 7. SILICOFLAGELLIDA. A single genus, Distephanus Stohr ('81), character- 

 ized by the presence of a silicious latticed skeleton like that of the Radiolaria. 

 There is no mouth nor modifications of the plasm whatsoever, but the animal is 

 colored yellow by (probably) diatomin. Parasitic on Radiolaria. 



Subclass II. DINOFLAGELLIDIA. Naked or shelled Mastigophora. There are 

 usually two flagella, of which one is directed away from the body, the other 

 around the body ; the shell usually has two furrows, one running transversely 

 around the body, the other vertically. Marine and fresh-water forms. The 

 nutrition is holophytic or holozoic. 



Order I . ADINIDA. The transverse furrow is absent, and the two flagella arise from 

 the anterior end of the body. The shell may be bivalved. 



Family i . Prorocentridae. With the characters of the order. Genera : Exuvi&lla 

 Cienk ( ? 82) ; Prorocentrum Ehr. ('33). 



Order 2. DINIFERIDA. Dinoflagellidia with two transverse furrows. 



Family i. Peridinidae. The cross furrow is near the middle of the body, which 

 may be with or without a shell. The form is extremely variable. Genera: 

 Podolampas Stein ('83) ; Blepharocysta Ehr. ('73); Diplopsalis Bergh ('82); 

 Peridinium Ehr. ('32) ; Goniodoma Stein ('83) ; Gonyaulax Diesing ( 1 66) ; 

 Ceratium Schrank (1793); Amphidoma Stein ('83) ; Oxytoxum Stein ('83) ; 

 Pyrophacus Stein ('83) ; Ptychodiscus Stein ('83) ; Protoceratium Bergh ('82) ; 

 Glenodinium Ehr. ('35) ; Gymnodinium Stein ('78) ; Hemidinium Stein ('78) ; 

 Steiniella Schiitt ('95); Monaster Schiitt ('95); Amphitholus Schlitt ('95). 



Family 2. Dinophysidae. The cross furrow is above the middle of the body, and 

 its edges are raised into characteristic ledges. Marine. Genera: Phalacroma 

 Stein ('83) ; Dinophysis Ehr. ('39) ; Amphisolenia Stein ('83) ; Citharistes 

 Stein ('83) ; Histioneis Stein ('83) ; Ornithocercus Stein ('83) ; Amphidinium 

 Clap, and Lach. ('59); Ceratocorys Stein ('83). 



Order 3. POLYDINIDA. The order consists of the single genus Polykrikos BUt- 

 schli ('73), which is characterized by a naked body, by several transverse furrows 

 and flagella, by macro- and micro-nuclei, and by nematocysts. Nutrition is 

 holozoic. 



Subclass III. CYSTOFLAGELLIDIA. Mastigophora of considerable size, with a 

 single nucleus, parenchymatous protoplasm, and a firm membrane. Nutrition is 

 holozoic. Marine. Genera: Noctiluca Suriray ('36); Leptodiscus R. Hertwig 

 C77). 



SPECIAL BIBLIOGRAPHY IV 



Biitschli, 0. Protozoa, Mastigophora. In Bronn's Klassen und Ordnungen des 



Thierreichs. Leipzig, 1883-1887. 



FrancS, R. H. Der Organismus der Craspedomonaden. Budapest h, 1897. 

 Kent, W. Saville. A Manual of the Infusoria. London, 1881. 

 Klebs, G. Flagellatenstudien i. Zeit.f. wiss. Zool, Bd. LV., pp. 265-445. 

 Schiitt, F. Die Peridineen der Plankton-Expedition. Th. I. Kiel and Leipzig, 



1895. 

 Senn, G. Flagellata. In A. Engler's Die naturlichen Pflanzenfamilien. 202 and 203 



Lieferung. Leipzig, 1900. 

 Stein, Fr. Der Organismus der Infusionsthiere. Leipzig, 1878. 



