356 
THE YOYAGE OF H.M.S. CHALLENGER. 
fossil species, is uniformly calcareous, hyaline, and perforate ; and excepting in certain 
varieties of Ehrenbergina, which are more or less beset with spines, the shell is free from 
external ornament or exostoses of any kind. 
Sub-family l. Textularinse. 
Textulana , 1 Defrance. 
Polymorpha, pars, Soldani [1791]. 
Textularia, Defrance [1824], Blainville, d’Orbigny, Rbmer, Reuss, Costa, Parker and Jones, Egger, 
"Williamson, Terquem, Karrer, Carpenter, Seguenza, Berthelin, Terrigi, &c. 
Textilaria, Ehrenberg [1839], Reuss, Stache, Karrer, Giimbel, Terquem, Sckwager, Hantken, 
Moebius, &c. 
Grammostomum , pars, Ebrenberg [1839], Kubler and Zwingli. 
Proroporus, Ebrenberg [1844], Reuss. 
Polymorphina, pars, Ebrenberg [1854]. 
RTiynehopleura (1), Ehrenberg [1856]. 
Plecanium, Reuss [1861], Karrer, Stache, Schwager, Giimbel, Hantken, Seguenza, M&rtonfL 
Textillaria, Schwager [1865], Martonfi. 
Cribrostomum, pars, Moller [1879]. 
The typical Textularian test consists of two rows of superimposed segments placed 
side by side, the segments of one row alternating with those of the other, and each seg- 
ment communicating with that immediately preceding and that immediately following it, 
in the opposite row. The normal aperture is a transverse arched fissure at the inner 
margin of the terminal segment, close to its line of union with the penultimate. In 
exceptional cases the opening is surrounded by a raised lip or border ; and specimens are 
also occasionally met with in which the later chambers have a small rounded terminal 
orifice, or even a number of pores scattered irregularly over the distal face, instead of the 
typical aperture. 
In the smaller species of Textularia the shell- wall is usually hyaline and perforate: 
in the larger varieties the test either remains calcareous and becomes thick and opaque, or 
it puts on an external coat of siliceous sand ; whilst some few species are entirely arena- 
ceous, and resemble in structure the coarser Lituolidce. Superficial ornament of any 
sort is very rare amongst the Textularia. Sometimes the sutures are marked externally 
by raised lines of shell-substance, and marginal or terminal spines are occasionally met 
with ; but, apart from these, the only true surface-ornament is in the case of two or three 
species which have either fine longitudinal striae or incomplete rounded costae. 
The geographical distribution of the genus Textularia is world- wide ; living specimens 
1 I prefer to retain the generic term in its original form, notwithstanding the criticism to which it has been subjected. 
The question is not whether Textilaria is a more elegant adaptation from the Latin than Textularia, or whether 
Texturinu, , as has been suggested, might not be better than either, but simply one of authority and precedence. 
