190 
THE VOYAGE OF H.M.S. CHALLENGER, 
The non-carinate variety of Ophthalmidium is altogether rarer than the carinate form 
previously described, and in the few localities in which it has been found it occurs in 
company with the latter species. The figured specimen is from the Challenger Station 
No. 24, off Culebra Island, West Indies, 390 fathoms. 
Hauerina, d’Orbigny. 
Hauerina, d’Orbigny [1846], Jones and Parker, Reuss, Karrer, Brady, Schwager, Steinmann. 
The genus Hauerina, reduced to its original d’Orbignian dimensions by the transfer 
to Planispirina of the species with Nummuline extensions of the chamber- walls, and to 
Ophthalmidium of the complanate forms with more distinctly Milioline characters, con- 
stitutes a compact and easily recognised group. It may be said to comprise the piano- 
spiral porcellanous Foraminifera which are Milioline only in the very early stages of 
growth, and have more than two segments in each of the later convolutions ; with smooth 
unornamented exterior, and porous aperture. 
The dimorphous habit, smooth exterior, and comparatively small number of segments 
serve to distinguish the genus from Peneroplis ; and the porous aperture, together with 
the absence of Nummuline lamination of the shell-wall, separate it from Planispirina. 
From Spiroloculina it is readily known by the number and arrangement of the chambers 
and by the aperture, notwithstanding certain intermediate forms, such as Spiroloculina 
fragilissima (PI. IX. figs. 12-14), which are an occasional source of difficulty. It is 
perhaps open to question whether the Cretaceous species described by Reuss, Hauerina 
antiqua , 1 with its large dome-shaped aperture, would not under the present arrange- 
ment be better placed in the genus Planispirina, but this can only be determined by 
the re-examination of the specimens. The Peneroplis laubei of Karrer, 2 appears to be a 
true Hauerina with somewhat embracing chambers. 
The geographical distribution of Hauerina is limited to the comparatively shallow 
waters of tropical and subtropical seas. Geologically, its earliest representative is the 
Cretaceous form already referred to, and less ambiguous species are found in the Miocene 
beds of the Vienna Basin (d’Orbigny, Karrer) and of the Banat (Karrer). 
Hauerina cornpressa, d’Orbigny (PI. XI. figs. 12, 13). 
“Testae hammoniformes, &c.” Soldani, 1789, Testaceographia, vol. i., pt. 1, p. 76, pi. lxix. fig. 1. 
Hauerina cornpressa, d’Orbigny, 1846, For. Foss. Vien., p. 119, pi. v. figs. 25-27. 
D’Orbigny’s description of Hauerina cornpressa needs but little modification to be 
equally applicable to recent and fossil specimens. In general terms the living examples 
of the species are somewhat larger and less regular in contour than those found in the 
1 Sitzungsb. d. k. Ak. Wiss. Wien, 1862, vol. xlvi. p. 35, pi. ii. fig 1, a, b. 
a Ibid., 1868, vol. lviii. p. 154, pi. iii. fig. 9. 
