REPORT ON THE FORAMINIEERA. 
545 
individual of the same species, and this may be correct, but it differs considerably from 
any young specimens that have come under my notice. 
The test of Cristellaria itcdica is elongate and trihedral ; the planospiral segments 
are few and inconspicuous, whilst those of the body of the shell are superimposed so as 
to form a curved line. The convex or dorsal margin is sharp but not carinate, and the 
ventral face is so broad that the transverse section of the shell has the form of a nearly 
equilateral triangle. The segments are short and obliquely set, dipping at the front 
more or less towards the initial end, as in Vaginulina. 
These characters in their fullest development separate Cristellaria italica in a striking 
manner from the helicoid members of the genus, but the connection of the entire group 
is maintained by an unbroken chain of intermediate varieties. Amongst the numerous 
broad-fronted passage-forms leading to the present species are Marginulina triangularis, 
d’Orbigny (For. Foss. Vien., p. 71, pi. iii. figs. 22, 23), Cristellaria arcuata (Id. Ibid., 
p. 87, pi. iii. figs. 34-36), Cristellaria vaginalis, Reuss (Sitz. d. k. Ak. Wiss. Wien, 
vol. xlviii. p. 50, pi. iv. fig. 49), and Cristellaria acutauricularis, F. and M., sp. (Test. 
Micr., p. 102, fig. 18, figs. g-i). 
Cristellaria italica has been taken at four Stations in the North Atlantic, at depths 
ranging from 390 fathoms to 725 fathoms, and at four in the South Pacific, 145 fathoms 
to 410 fathoms. In certain localities, notably off Culebra Island, West Indies, and off 
Kandavu, Fiji Islands, the specimens attain large dimensions, and are sometimes as 
much as -|th inch (5 mm.) in length. It occurs also in the Mediterranean, 90 fathoms, 
and in the comparatively shallow water of the Adriatic. There is no record of its 
presence in the South Atlantic, the North Pacific, or the Southern Ocean. 
The species has been found in the Cretaceous formations of the north of Ireland 
(Wright), in the London Clay (Parker and Jones), and in the later Tertiaries of Austria, 
Italy, and Spain (d’Orbigny, Parker and Jones, Seguenza). 
Cristellaria italica, var. volpicellii, Costa (PL LXVII. fig. 9, a.b.). 
Cristellaria volpicellii, Costa, 1855, Mem. Acad. Sci. Napoli, vol. ii. p. 120, pi. i. 
fig. 4, a.b. 
The original drawing of Cristellaria volpicellii represents a short variety of Cristellaria 
italica, with carinate dorsal margin and thick, clear, septal lines. The specimen appears 
to have been somewhat more curved than the recent shell portrayed in PI. LXVII., but 
the figures agree perfectly in other respects. 
The only habitat at which this carinate variety has been observed is Station 335, 
South Atlantic, mid-ocean, depth 1425 fathoms. 
The type specimens described by Costa were obtained from the Blue Vatican Marl of 
Rome. 
