540 
THE VOYAGE OF H.M.S. CHALLENGER. 
Cristellaria dentata, Karrer (PL CXIII. fig. 12, a.h.). 
Cristellaria dentata , Karrer, 1867, Sitzungsb. d. k. Ak. Wiss. Wien, vol. lv. p. 348, pi. i. fig. 1. 
,, nummuliiica , Hantken, 1875, Mittheil. Jalirb. d. k. ung. geol. Anstalt, vol. iv. p. 
51, pi. vi. fig. 4, a.b. 
There need be no hesitation, I think, in referring the figured specimen (PI. 
CXIII. fig. 12) to this species, notwithstanding its somewhat stouter proportions and 
the nearly even outline of the carina. The irregularly dentate margin represented in 
Dr. Karrer’s drawing is an accidental feature, not unfrequent amongst the carinate species of 
Cristellaria (see PI. LXX. figs. 7, 8), and of little importance from a zoological point of 
view. The recent shell is more solidly built, and this is observable not only in the general 
conformation of the test but also in the greater thickness of the septa. 
Morphologically speaking, Cristellaria dentata may be regarded as the typical or 
smooth form of Cristellaria semiluna, cTOrbigny (For. Foss. Vien., p. 90, pi. iii. figs. 43, 
44) and only differs from that species by the absence of the costate surface-ornament. 
The figures referred by von Hantken ( loc . cit.) to Cristellaria nummulitica have more in 
common with the present form than with the specimens figured by Giimbel under that 
name. 
The single recent example of the species was taken off Kandavu, 210 fathoms, a 
locality wonderfully rich in Cmstellarice. 
The fossil specimens obtained by Karrer and Hantken were from deposits of Middle 
Tertiary age in Austria and Hungary. 
Cristellaria tricarinella, Reuss (PI. LXYIII. figs. 3, 4) . 
Cristellaria tricarinella, Reuss, 1862, Sitzungsb. d. k. Ak. Wiss. Wien, vol. xlvi. p. 68, pi. vii. 
fig. 9, and pi. xii. figs. 2-4. 
„ protosphcera, Id. Ibid. p. 68, pi. vii. fig. 8 ; and pi. xii. fig. 10. 
„ truncana, Giimbel, 1868, Abhandl. d. k. bayer. Akad. d. Wiss., II. Cl. vol. x. p. 
639, pi. i. fig. 68, a.b. 
This is a handsome, somewhat elongate species, thin and complanate, with nearly 
flat sides and limbate sutures, and sometimes showing a narrow but well-defined marginal 
keel. The peripheral margin is more or less limbate, as well as the septal lines, and the 
term “ tricarinella” is not altogether inappropriate for carinate specimens. 
The presence or absence of the marginal keel forms the chief distinction between 
Reuss’s Cristellaria tricarinella and Cristellaria 'protosphcera, and the two specimens 
represented in PI. LXYIII. figs. 3 and 4, would therefore be assigned one to each species 
were this accepted as a reliable character. But, judging by the recent examples, both the 
carina and the inflated primordial segment portrayed in some of the original figures are 
features far too uncertain and variable to have any really distinctive value. 
