Nomenclature of the Foraminifera. 93 



fig. 15, and pi. 9. fig. 15 c, p. 196) ; and Bigenerine Textularia 

 with a coiled commencement occur in Baffin's Bay. So also T. 

 carinata, D'Orb., is often coiled in its early stage, especially the 

 specimens found in the London Clay ; and the coiled condition 

 of Grammostomum capreolus, D'Orb., is well and boldly illus- 

 trated by Soldani in his ' Testaceograph.' vol. i. part 2, pi. 108. 

 G. capreolus and its subvarieties may be either coiled and bi- 

 serial, or coiled, biserial, and uniserial (offering a form equivalent 

 to Textularia annectens), or bi- and uniserial without the coil. 

 It is often sandy, and of a large relative size ; it occurs in the 

 West Indies, and abounds in the Adriatic. 



Some of the shells arranged as Gaudi-yina (for instance, G. 

 siphonella, Reuss) have their triple series of chambers so twisted 

 on the axis as to have a Buliminoid aspect. We possess a very 

 beautiful specimen of this kind from the Tertiary beds of San 

 Domingo. A slight approach to this condition occurs in the 

 Vemeuilina polystropha [Bulimina po It/strop ha, Reuss), which we 

 have found to be very common in the living state in Davis's 

 Straits (Baffin's Bay), St. George's Bay (Beyrout), Syra (Greek 

 Archipelago), Abrolhos Bank, &c. 



A large proportion of the Textularia may be clear-shelled and 

 tubuliferous, as the smaller individuals of Textularia proper, 

 Grammostomum, and Verneuilina. Others are opake-shelled, 

 because arenaceous. The calcareous cement of the shell-matter 

 in many ( Verneuilina polystropha and Bigenerina digitata) is of a 

 ferruginous colour in the recent state, the substance of the shell 

 having the rusty-red colour of the recent Lituola — a colour 

 which, with other tints, occurs in both opake and clear-shelled 

 Foraminifers*. 



All the larger varieties of Textularia are arenaceous ; but 

 there is a host of small forms (many of which have been ho- 

 noured by authors with specific appellations) entirely free from 

 foreign matter, the shell being composed of finely perforated 

 clear substance. These are at first sight often undistinguishable 

 from D'Orbigny's Bolivina (which may be said to be Textulari- 

 form Bulimina). The larger forms, T. truchu^, T. turris, T. ng- 

 glutinans, and T. gibhosa (essentially hyaline in their shell- 

 structure), strengthen themselves not only with sand-grains, but 



* The same species of Foraminifera may be very variable in tint when 

 taken from different habitats. Orbitolites may be either rust- coloured, 

 livid, or pink (usually the last). In Miliola the aperture is sometimes 

 rusty ; and sandy specimens are sometimes altogether rust-coloured, espe- 

 cially Quinqueloculina agylutinans. Peneroplis is pink when alive. Alveo- 

 lina is sometimes pink, sometimes rusty. Globigerina has a beautiful pink 

 colour. Planorbulina farcta is livid or purplish in the Mediterranean, 

 P. vulgaris of Australia is livid ; in the Indian Sea it is rosy pink ; and 

 often it is destitute of colour. 



