Nomenclature of the Foraminifera. 477 



lince. C. cultrata and C. Cassis are lenticular and discoidal shells 

 with a marginal crest or keel very variable in extent. The terms 

 Robulina, Saracenaria, and Planularia have been applied to some 

 of the Cristellarian varieties. 



In essential characters of stnicture and mode of growth, the 

 Cristellaria and Nodosaria are one ; and the Glandulina, Lingu- 

 lirue, DentalincB, Rimulinee, Vaginulina, MarginulincB, Dimorphirue, 

 Flabellince, and Frondicularics of authors necessarily fall in the 

 same category. We propose to use the term Nodosarina as ex- 

 pressive of the type-species, including all the above. We adopt 

 Cristellaria and Nodosaria as subspecific appellations, — the 

 former comprising the spiral (or Nautiloid, Marginuline, and 

 Flabelliue) forms ; the latter taking those that have a rectilinear 

 or only slightly curvilinear arrangement of the loculi. It is 

 impossible, however, to make a strict line of demarcation between 

 the approximate members of the group, since the straight, the 

 curved, and the spiral lose themselves in each other, — the amount 

 of curvature and of spirality, and the greater or less closeness of 

 the whorls being varying characters. 



Cristellaria Calcar and its multitudinous varieties have a very 

 wide geographical range, and occur fossil in the tertiary, creta- 

 ceous, oolitic, liassic, and upper triassic* strata. The finest living 

 Cristellaria occur in the Adriatic, and the finest fossil specimens 

 in the tertiaries of Italy, Spain, and San Domingo. Large 

 individuals, however, have been met with on the Norway coast, 

 on the coast of New York, and on the Abrolhos Bank. Moderate- 

 sized specimens are extremely numerous in the London Clay and 

 in the Chalk. For the synonymy of C. Calcar, see our paper in 

 the ' Annals,^ loc. dt., and especially Williamson^s ' Monograph/ 

 p. 29. 



(B. a.) Of the Nodosarice we find several varieties enumerated 

 by Linnseus. The first in his list is Nautilus obliquus (1 163. 281 ), 

 established on a curved, tapering, ribbed Nodosaria figured by 

 Gualtieri (Index Test. pi. 19. fig. N). N. Raphanistrum (1163. 

 282) and N. Raphanus (116-i. 283) follow. These are slightly 

 varying forms of the common, straight, ribbed Nodosaria, — the 

 chambers varying in their relative number and their globosity 

 (or, rather, in the closeness of their setting-on), the aperture vary- 

 ing from a central to a sublateral or excentric position, and the 

 riblets varying in relative size and number. 



The figures, by Plancus, Gualtieri, and Ledermiiller, on which 

 Linne founded his species, or which he referred to as synony- 

 mous, show these variations; and scarcely two individuals 

 of this group of Nodosaria can be found in nature presenting 

 identical conditions in these respects; but all vary from the 



* We have lately discovered numerous Foraminifera in the greenish 

 davs of the New Red series near Derbv. 



