TEXTILARIA AGGLUTINANS. 149 



Textttlaria agglutinans, Egger, 1893. Abhandl. k. Akad. Bayer., vol. xxviii, 



part 2, p. 267, pi. vi, figs. 1 and 2. 

 (Thick, trochoid.) 

 — — Goes, 1891. K. Svensk. Vet.-Akad. Handl., vol. xsv, 



No. 9, p. 35, pi. vii, figs. 281— 284, 

 291—303. (Fig. 300 seems to be 

 typical, the others varieties.) 



Characters. — Shell elongate, conical, suboblong in section ; chambers more or 

 less horizontal and compact, presenting a broad or narrow pentagonal aspect on 

 the sides of the shell. The chamber-cavities liable to subdivision by secondary 

 septa (see fig. 16), which form barred apertures. Shell-wall consisting of 

 agglutinated sand-grains. 



This form, which we regard as the type of the genus, is variable in its features 

 to a considerable extent. Extreme forms are illustrated by the tapering and 

 slightly flexed fig. 14 of PI. Ill ; the short subcylindrical form in the ' Phil. Trans.,' 

 1865, pi. xv, fig. 21 ; and the longer subcylindrical T. parallela, Reuss ; the 

 compressed T. laevigata, d'Orb., and T. concinna, Reuss, and the shorter T. contra 

 and pupa, passing into T. Partschii, which is evidently related to T. gibbosa and 

 tuberosa, d'Orb. On the other hand, T. agglutinans may be compressed, as 

 Plecanium eocsenum, Giimbel. 



D'Orbigny's figures, from recent examples, very much resemble our PL III, 

 figs. 14, 15, the latter being perhaps a little rougher and more irregular; but 

 proportionately shorter specimens are often met with. The labyrinthic condition 

 shown in section in fig. 16 is not uncommon in other varieties of the genus, under 

 circumstances favorable to the production of large free-growing specimens. A 

 similar state of the terminal orifice is one of the peculiar characters of the tropical 

 Textilaria Barrettii. 



Occurrence. — Textilaria agglutinans is found in all seas and at all depths ; the 

 lowest recorded depth is 3125 fathoms. The geological range of this species has 

 lately been shown to extend from the Neocomian (Bargate Beds) of Surrey 

 (Chapman). It has been found also in the Gault of Folkestone, the Red Chalk of 

 Speeton, the White Chalk, the Eocene London Clay, the Oligocene of Elsass, the 

 Miocene of Vienna and of Muddy Creek in Victoria, the Older Tertiaries of South 

 Australia (Howchin), the Helvetian and Plaisancian beds of Italy (de Amicis), 

 and in the Pleistocene of Sicily (Seguenza). We have found specimens in every 

 zone of the Coralline Crag examined except at Tattingstone. In Mr. S. V. Wood's 

 Sutton gatherings the specimens are numerous and large. 



