FAMILY 6. REOPHACIDAE 91 



Genus OPHIOTUBA Rhumbler, 1894 



Genoholotype, Ophiotuba gelatinosa Rhumbler 

 Ophiotuba RHUMBLER, Zeitschr. Wiss. ZooL, vol. 57, 1894, p. 604. 



Test attached to the interior of larger foraminiferal tests, 

 irregularly winding ; wall chitinous ; aperture at the open end of 

 the tube. 



Recent. North Sea and Atlantic Ocean, 40-520 meters depth. 



Genus DENDROTUBA Rhumbler, 1894 

 Plate 6, figure 18 



Genoholotype, Dendrotuba nodulosa Rhumbler 

 Dendrotuba Rhumbler, Zeitschr. Wiss. Zool., vol. 57, 1894, p. 606. 



Test attached to the interior of other foraminif era, irregularly 

 winding and anastomosing; wall chitinous; apertures, the open 

 ends of the tubes. 



Recent. North Sea and Atlantic Ocean, 40-520 meters depth. 



The foraminif era included in this family have their beginnings 

 well back in the Palaeozoic. The simple globular proloculum 

 followed by an elongated, undivided second chamber is a primi- 

 tive character. From forms such as Hyperamynina by division 

 of the tubular chamber have come the Reophacidae, a family 

 which also developed very early in the geologic series. 



FAMILY 6. REOPHACIDAE 



Test consisting of either an irregular or a generally rectilinear 

 series of chambers, typically increasing in size as added, simple 

 or labyrinthic ; wall chitinous with usually an exterior of agglu- 

 tinated material, sand grains, sponge spicules or the tests of 

 other foraminifera ; aperture usually terminal, simple or 

 multiple. 



KEY TO THE GENERA 



I. Chambers irregular in size and arrangement. 



A. Wall chitinous, test in the interior of other foraminifera. 



Hospitella. 



