Foraminifera from the Coast of Norway. 295 



19. CassiduUna Iceviffata, D'Ovh. PI. XI. figs. 17, 18. 

 Cassidulina lavigatq, D'Orb. Ann. Sc. Nat. vii. p. 2H2. pi. 15. f. 5 & 6. 



Shell suborbicular, smooth, hyaline; the Norway specimens 

 are rather flattened and have the edge of the shell sharp. 

 Chambers more or less oblong, alternating in a double series 

 along an axial line, and the whole arranged irregularly on a spiral 

 plan, so that the earher-formed chambers are at intervals tres- 

 passed upon and partially overcrossed by succeeding chambers 

 formed at a very different angle from that of their predecessors ; 

 hence some of the chambers appear as if they w^ere small and 

 intercalated. In the Norway specimens about 8 to 11 cham- 

 bers are apparent. Aperture a narrow curved slit towards the 

 spire and parallel with the lower edge of the chamber, the 

 terminal face of which is flat and oblique. The aperture has a 

 partial projecting valve-like lip. 



This Cassidulina is excessively abundant in Shetland, where 

 it runs into a thickened and nearly orbicular form (C. crassa, 

 D'Orb.) ; also at Skye, Whitehaven, &c. It occurs fossil at 

 Turin, Palermo, and 13ordeaux ; and indeed usually accompanies 

 NonionincB. 



20. Valvulina triangularis, D'Orb. PI. XI. figs. 15, 16. 



Valvulina triangularis , D'Orb. Ann. Sc. Nat. vii. p. 2/0. no. 1 ; Modeles, 

 no. 25. 



Shell opake and arenaceous, red with rust-coloured particles 

 with which it is studded. In the young state, circular and conical ; 

 cone broad at the base, and somewhat concave both at sides and 

 base ; basal edge sharp ; apex of cone formed of the relatively 

 large globular first chamber, and almost separated from the 

 rest by a slight constriction. Cone formed of 7 or 8 flattish, 

 almost semicircular chambers, increasing rapidly in size, ar- 

 ranged in a spiral manner; three chambers completing each 

 circuit of the spire ; and three being exposed at the base of the 

 cone (youngest portion of the shell). Aperture an irregular 

 slit, under the central two-thirds of the edge of chamber, and 

 accompanied by a slightly raised lip or " opercular valve." 



This form is small and rare in the Norway dredgings ; but it 

 occurs of larger size in Australia, and comparatively gigantic in 

 some of the French Tertiaries (Hautville, &c.). It is common 

 also in the West Indies. The cone in these instances varies 

 considerably in its relative proportions, but always retains its 

 characteristically globular apex (first chamber). A more highly 

 developed form of the species (which always presents an are- 

 naceous condition of shell) occurs in company with the conical 

 form in Australia and the West Indies, and also in the French 



