436 
THE VOYAGE OF H.M.S. CHALLENGER. 
classed with, the Nodosarince ; hut, as I have elsewhere shown, 1 this has not proved to he 
the fact, for the orifice occupies an independent position at its base, and the column itself 
is not hollow, hut it is often deeply grooved longitudinally, or even split into two or three 
parts near the upper extremity. No example of the genus Ellipsoidina has hitherto 
been found in the recent condition ; indeed it is known only by a single species, Ellipsoidina 
ellipsoides, Seguenza, the occurrence of which, so far as at present known, is confined to 
the Miocene formation of the neighbourhood of Messina. 
Chilostomella, Eeuss. 
Chilostomella, Reuss [1849], Bornemann, Karrer, Hantken, Norman, Schwager, Brady, Siddall, 
Biitsclili. 
The genera Chilostomella and Allomorphina were established by Reuss on the basis of 
fossil specimens obtained from the Tertiary deposits of Austria and Germany, and were 
originally placed in d’Orbigny’s Family, Enallostegia, between Polymorphina and 
Textidaria. . Subsequently, however, they were found to have so little in common with 
these, or indeed with any other known types of perforate Foraminifera, that in the later 
schemes of classification proposed by the same author they were removed from that 
position to form a distinct family. 
Although the specimens included in the genus Chilostomella present considerable 
diversity of contour and vary also in some of their less important characters, there 
need be no hesitation in assigning them all to a single species ; and the subjoined account 
of Chilostomella ovoidea serves equally as the description of the generic group. 
Chilostomella ovoidea, Reuss (PI. LV. figs. 12-23). 
Chilostomella ovoidea, Reuss, 1849, Denkschr. d. k. Akad. Wiss. Wien, vol. i. p. 380, pi. xlviii. 
fig. 12, a.-e . 
,, czjzehi, Id. Ibid., p. 380, pL xlviii. fig. 13, a.-d. 
„ cylindroides, Id. 1851, Zeitschr. d. deutsch. geol. Gesellsch., vol. iii. p. 80, pi. vi. 
fig. 43. 
„ „ Bornemann, 1855, Ibid., vol. vii. p. 343, pi. xvii. fig. 1. 
,, tenuis. Id. Ibid. p. 343, pi. xvii. fig. 2. 
,, oolina, Scbwager, 1878, Boll. R. Com. Geolog., Nos. 11, 12, p. 10, pi. i. fig. 16. 
„ ovoidea, Brady, 1879, Quart. Jo-urn. Micr. ScL, vol. xix., N. S., p. 66, pi. viii. 
figs. 11, 12. 
The test of Chilostomella ovoidea is composed of a number of ovate or elliptical 
chambers, each a good deal larger than its predecessor ; and each succeeding chamber 
encloses nearly the whole of the previous one, except a small portion at one end. The 
chambers are attached to each other at one side of the shell, and their direction of growth 
alternates, that is to say, they are put on first at one end and then at the other. The 
external line of union between the two visible segments is not directly transverse, but 
1 Ann. and Mag. Nat. Hist., ser. 4, vol. i. p. 333 et seq. , pi. xiii. 
