FORAMINIFERA OF THE ATLANTIC OCEAN. 7 



Subfamily 1. Astrorhizinae. 



Test consisting usually of a tube open at both ends or in some spe- 

 cies of Astrorhiza with several tubes entering a central chamber; in 

 some species with the tube branching {Rhabdammina, irregularis, 

 Rhizammina algaeformis, etc.). 



Included in this subfamily are live genera, Astrorhiza, Rhabdammina, 

 Marsipella, Bathy siphon, and Rhizammina. With the exception of 

 the first, we know very little concerning the animal, excepting for the 

 material of which the test is made; each consists of a simple or 

 branching tube open at the ends, except in some species of Astrorhiza, 

 whore there are several tubes and a single central chamber. The 

 growth seems to take place by the addition of material at the open 

 ends of the tube, thus increasing the length. The openings are 

 often variously protected by an accumulation of foreign particles, 

 sponge spicules, etc. 



Genus ASTRORHIZA Sandahi. 1857. 



Astrurhiza Saxdahl {type, Astrorhiza limicola Sandahlj, Ofv. Svun.sk. Vet. Akad, 

 Forh., vol. 14, No. 7, 1857, p. 299.— H. B. Brady, Rep. Voy. Challenger, 

 Zoology-, vol. 9, 1884, p. 230.— Flint, Ann. Rep. U. S. Nat. Mus., 1897 (1899), 

 p. 265.— Rhumbler, Arch. Prot., vol. 3. 1903, p. 216.— Cushman, Bull. 71, 

 U. S. Nat. Mu8., pt. 1, 1910, p. 19. 



Aslrorhiza+Rhahdamjnina (part) Eimki: and Fickeut, Zeitschr.wTss. Zool., vol. 65, 

 1899, p. 666. 



Ammodiscus Carpenter and Jeffreys, Proc. Roy. Soc. London, 1870, p. 159 

 (not Ammodiscus Reiiss, 1871). 



Arenistella Flscher and dk Folin, Les Fonds de la Mer, vol. 2, 1872, p. 26. 



Astrodiscus F . E. Schulzk, 11 .lahr. Comni. wis. Unt. deutsfh. .Meer in Kiel, vol. ], 

 1875, p. 113. 



Ilaccl-clina Be.ssels, Jen. Zeitschr., vol. 9, 1875, p. 265. 



Descnption. — Test free, flattened or tubular, stellate or subcylin- 

 drical, composed of a central chamber with communicating tubular 

 portions to the exterior in the compressed species or of an irregular 

 tubular chamber in the subcylindrical ones; wall composed of sand 

 or mud loosely cemented, often with an inner lining of chitinous 

 material. 



Most of the species appear to be characteristic of cool-water condi- 

 tions, although A. vermiformis is a species apparently as far as is 

 known limited to the Gulf of Mexico, 



ASTRORHIZA LIMICOLA Sarnlahl. 



Plate ] .[figs. 1, 2. 



Aslrorhiza liinicolu i>\si)Anh, OfverH Kongl. V'ctenskaps-.Vkad. Forhandl., vol. 14. 

 1857, p. 299, pi. 3, figs. 5, 6.— Leidy, Proc. Acad. Nat. Rci. Philadelphia, 1875, 

 p. 65, fig. —P. Fisher, Journ. Zool., vol. 4, 1875, p. 505, pi. 16, figs. 1-4. — 

 Norman, Proc. Roy. Soc. I^ndon, vol. 25, 1876, p. 213.— H. B. Brady, 

 Quart. Journ. Micr. Sci., vol. 19, 1879, p. 43.— Butsciim, in Bronn, Kla.'^.sen 



