PHYLUM PROTOZOA 39 



Typical genera: Astrorhiza, Sandahl, 1857'; Syringammina, Brady, 1884; Pilu- 

 lina, Carpenter, 1862; Saccammina, Sars, 1868; Rhabdammina, Sars, 1868; 

 Haliphysema, Bowerbk., 1862; Marsipella, Norman, 1878. 



Order 3. Lituolida. Lister recognizes four families. Here the test is arenaceous, 

 usually regular, mono- or polythalamous. Lister notes that it comprises 

 sandy isomorphs of certain types of hyaline or porcellanous forms. 



Typical genera: Lituola, Lamarck, 1801; Rheophax, Montfort, 1808; Haplo- 

 phragmium, Reuss, 1860; Hippocrepina, Parker, 1870; Polyphragma, Reuss, 

 1860; Cyclammina, Brady, 1884; Loftusia, Brady, 1884; Parkeria, Carpenter, 

 1862. 



Order 4. Miliolida. Lister recognizes six families. Here the test is typically 

 calcareous and hyaline, but may be covered with sand or detritus. 



Typical genera: Cornuspira, M. Sch., 1854; Spiroloculina, D'Orb., 1826; Tri- 

 loculina D'Orb., 1826; Vertebralina, D'Orb., 1826; Articulina, D'Orb., 

 1826; Peneroplis, Montfort, 1810; Orbiculina, Lamarck, 1801; Orbitolites, 

 Lamarck, 1801; Alveolina, D'Orb., 1826; Keramosphera, Brady, 1884; 

 Nubecularia, Defrance. 



Order 5. Textulahida. Lister recognizes three families. Here the chambers 

 are arranged in one or two series, which may be alternate, spiral, or irregular; 

 arenaceous and with or without a perforated calcareous basis. 



Typical genera: Textularia, Defrance, 1824; Valvulina, D'Orb., 1826; Virgulina, 

 D'Orb., 1826. 



Order 6. Chilostomellida. Lister has three genera. The test is calcareous, 

 polythalamous and finely perforated. 



Typical genera: Chilostomella, Reuss, 1860; Allomorphina, Reuss, 1860. 



Order 7. Lagenida. Lister recognizes four families. Here the test is similar to 

 the last save for the monothalamous shell, which, however, may be compound 

 by the union of chambers end to end in a straight or curved series. Canals 

 and canalicular skeleton wanting. 



Typical genera: Lagena, Walker, and Boys, 1784; Nodosaria, Lam., 1801; Poly- 

 morphina, D'Orb., 1826; Ramulina, R. Jones, 1875. 



Order 8. Globigerinida. Not divided into families. The test is perforated and 

 calcareous, with few chambers arranged in a spiral. Canals and canal 

 system absent. 



Typical genera: Globigerina, D'Orb., 1826; Orbulina, D'Orb., 1826. 



Order 9. Rotalida. Lister recognizes three families. The test is calcareous and 

 perforated, with all of the chambers visible from one aspect, and arranged in 

 a spiral; some of the more highly developed forms with canal system. 



Typical genera: S^mWma, Ehr., 1841 ; Discorbina, Parker and Jones, 1862; 

 Calcarina, D'Orb., 1826; Rotalia, Lamarck, 1801; Tinoporus, Carpenter, 

 1857; Carpenteria, Gray, 1858. 



Order 10. Nu.mmulitida. Lister recognizes three families. Here the test is 

 calcareous, filled with tubules, and bilaterally symmetrical (except Amphis- 

 tegina), and with canal system in the higher forms. 



Typical genera: Fusulina, Fischer, 1829; Polystomella, Lamarck, 1822; Oper- 

 culina, D'Orb., 1826; Nummulites, Lamarck, 1801; Orbitoides, D'Orb., 

 1826 (Fig. 9, p. 26). 



Subclass 4. Amebea. Here are included the more common forms of rhizopods 

 with blunt or lobose pseudopodia which do not anastomose on touching one 

 another, a physiological character which indicates a well-marked difference 

 in the different types of rhizopods. The protoplasmic body may bear shells 

 or not. 



Order 1. Gymnamebida. Here the body is uncovered, although there is, in many 

 cases, a tendency of the peripheral plasm to harden into a denser, mem- 

 brane-like zone which approaches the simpler forms of tests. 



