78 GOÉS, RETICULAllIAN RRIZOPODA OF THE CARIBBEAN SEA. 



Syn. Textularia Partschii Cz.iz., 1847, Foramf. Wien. Beck.: Haid. Nat. Abh. 2. i, p. 148, t. 13, figg. 



22—24. 



» pupa Rss., 1859, Westphäl. Kreide; Wien. Ak. Sitz.-Ber. 40, p. 232, t. 13, figg- 



4—5. 

 » strombus, peocetia, elypeata, erassa Costa 1854, Pal. Nap. 2, p. 293—296, t. 13, 



fig. 34, t. 23, figg. 4, 6, 7. 

 Plecanium Karreri, granosissimuin, eurystoma Sxache, 1865, Tert. ]\'Ierg. Wliaingar. Hafen; No- 

 vara Eeise, geol. Tli. 1. 2, p. 179, t. 21, figg. 17—19. 

 Grammostomum depressum etc. Ehrenb., 1854, Microgeol., t. 19, Rs. 82; t. 25, figg. 8 — 12; t. 28, 



fig. 31; t. 32, figg. 5, 9, 10. 

 Spiroplecta amerieana Ehrenb., ibid. t. 32, fig. 25. 



b) s t r i a t a : 



Textularia striato-punctata Egger, 1857, Mioo. Ortenlnirg; Leonli. u. Bronn. Jlirb. 1857, p. 294, 



t. 12, figg. 27—29. 

 (Nominitaus variis) Ehrenb., 1854, Mikrogeol. t. 27, figg. 3 — 5. 



Spiroplecta amerieana Ehrenb., ibid. t. 32, ligg. 13 — 14. 



c) a c u 1 e a t a : 

 Textularia aculeata etc. Euiienb., 1854, t. 29, figg. 20. a. b. 



Forma bigenerina d'Orb. 



Bigenerina Isevigata u'Orij., 1826, Tab. meth.; An. Se. Nat. 7, p. 261. 



» ampla Kaur., 1877, Hoohqueilenwasserleit.; Osterr. geol. Ueiclisaust. Abh. 9, p. 374, 



t. 16, fig. 374. 

 » patula Brady, 1876, Carb. and Perrn. förf.; Pal. Soc. 30, p. 136, t. 8, figg. 10—11. 



t. 10, figg. 30—31. 



Textularia sagittula Defk. fomui Bigenerina. 



Tab. V, figg. 159—161. 



Is liable to great variation in size, form and condition of its surface, depending 

 on the greater or less developinent of the textularia-stage and on the coarseness or 

 fineness of the constituents of the sea-bottom which have been agglutinated. It hap- 

 pens often that the textnlaria-stage is very atrophic and the chambers are difficult to 

 trace. Our form from the chalk-bottom contains not seldom great many spongia 

 spicula agglutinated with shell- and chalk-debris, so that de surface is quite bristly. 

 The aperture is generally orbicular and central; but sometimes it is semilunar in 

 shape. Among several represensations given by different authors of »Bigenerina^» we 

 have not been able to find any, that full}' agrees with our form. Bigenerina torulosa 

 Costa is the nearest to our coarser specimens, but his is thicker. 



It is very common in both coralline-gravel and chalk-ooze, and attains a length 

 of 5 — 6 mm. 



