334 
THE YOYAGE OF H.M.S. CHALLENGER. 
point southwards to which it has been traced is off Christmas Harbour, Kerguelen 
Island, 120 fathoms. Notes have been made of its presence at twenty-seven 
Challenger Stations, of which ten are at depths of more than 2000 fathoms, and five 
others at more than 1000, the remainder ranging from 50 fathoms downwards. 
In the fossil condition it has been found in the Carboniferous rocks of England, 
Scotland, and Belgium, and in the Permian Magnesian Limestones of the north of England. 
It is figured by Kiibler and Zwingli and by Haeusler from the Jurassic beds of Switzerland, 
and by Karrer from the Early Tertiary Vienna Sandstones. 
Ammodiscus charoides, Jones and Parker, sp. (PL XXXVIII. figs. 10-16). 
Trochammina sqiiamata cliaroides, Jones and Parker, 1860, Quart. Journ. Geol. Soc., vol. xvi. 
p. 304. 
„ charoides, Carpenter, 1862, Introd. Forarn., p. 141, pi. xi. fig. 3. 
,, proteus (pars), Karrer, 1866 Sitzungsb. d. k. Ak. Wiss. Wien, vol. liii. p. 
494, pi. i. fig 4. 
Cornuspira reussi, var. excenirica, Reuss, 1870, Ibid., vol. lxii. p. 464. — Schlicbt, 1870, Foram. 
Pietzpuhl, pi. xxxv. figs. 13-23. 
Trochammina charoides, Siddall, 1878, Proc. Chester. Soe. Nat. Sci., pt. ii. p. 47. 
Ammodiscus charoides, Berthelin, 1878, Foram. de Bourgneuf et Pornichet, p. 23, No. 18. 
Trochammina charoides, Haeusler, 1882, Ann. and Mag. Nat. Hist., ser. 5, vol. x. p. 56, pi. iv. 
fig. 21. 
Test free, spiral, rounded ; subglobular or biconvex ; consisting of a tube of nearly 
even diameter coiled regularly upon itself in a compact series of vertical layers, 
resembling externally the nucule of Cliara. Colour brown, surface smooth and glossy. 
Aperture the open or slightly constricted end of the tube. Diameter, -^th inch (0'34 mm.). 
Ammodiscus charoides is of smaller dimensions than either of the two species previously 
described ; its structural features also are somewhat more complicated, and will be 
better understood from the drawings than from verbal description. Morphologically 
speaking, it occupies an intermediate position connecting Ammodiscus incertus with 
Ammodiscus shoneanus, the former of these being flat and planospiral, the latter 
cylindrical and vertically spiral, whilst Ammodiscus charoides is subglobular, and the 
arrangement of its convolutions is to some extent both complanate and vertical. 
Ammodiscus charoides is by no means a common species, though it is distributed over 
a very wide area, and presents an extensive bathymetrical range. It has been found in the 
Faroe Channel, 530 fathoms, in the estuary of the Dee (Siddall) ; on the shores of the Bay 
of Biscay (Berthelin), and at three Challenger Stations in the North Atlantic, 450 to 1750 
fathoms. Parker and Jones record its occurrence in the Red Sea, and at seven 
localities in the Mediterranean, 90 to 1700 fathoms. It has been noticed at three Stations 
in the South Atlantic, 1900 to 2350 fathoms ; also between the Cape of Good Hope and 
