78 GOES, KKTIOULAUIAN KKI/OPOPA OF THE CARIBBEAN SEA. 



Syn. Textularia Partschii GZJZ., 1847, Foramf. Wieti. Bock.; Haid. Nat. Abh. 2. i, p. 148, t. 13, figg. 



2224. 

 pupa Rss., 1859, Westphal. Kreide; Wien. Ak. Site.-Ber. 40, p. 232, t. 13, figg- 



45. 

 strombus, peocetia, clypeata, crassa COSTA 1854, Pal. Nap. 2, p. 293 296, t. 13, 



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

 Plecanium Karreri, granosissimum, eurystoma STACHE, 1865, Tert. Merg. \Vliairigar. Hafen; No- 



vara Reise, geol. Th. 1. 2, p. 179, t. 21, figg. 1719. 

 Grammostomum depressum etc. EHRENB., 1854, Microgeol., t. 19, flu. 82; t. 25, figg. 8 12; t. 28, 



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

 Spiroplecta americana EHRENB.. ibid. t. 32, fig. 25. 



b) striata: 



Textularia striato-punctata EGGER, 1857, Mioc. Ortenhurg; Leonh. u. Bronti. Jhrb. 1857, p. 294, 



t. 12, figg. 2729. 



(Nominibus variis) EHRENB., 1854, Mikrogeol. t. 27, figg. 3 5. 



Spiroplecta americana EIIKENB., ibid. t. 32, figg. 13 14. 



c) aculeata: 



Textularia aculeata etc. EHRENB., 1854, t. 29, tigg. 20. a. b. 



Forma bigenerina D'OitB. 



Bigenerina Isevigata D'OKB., 1826, Tab. meth.; An. Sc. Nat. 7, p. 261. 



ampla KAIIR., 1877, Hochquellenwasserleit.; Ostcrr. gcol. Reichsaust. Abh. 9, p. 374, 



t. 16, fig. 374. 

 patula BRADY, 1876, Garb, and Perm, forf.; Pal. Soc. 30, p. 136, t. 8, figg. 1011. 



t. 10, figg. 3031. 



Textularia sagittula DEFK. forma Bigenerina. 



Tab. V, figg. 159161. 



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

 on the greater or less development 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 textularia-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 Lri 

 shape. Among several represensations given by different authors of Bigenerinae we 

 have not been able to find any, that fully 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. 



