144 FORAMINIFERA OF THE CRAG. 



Textularia sagittula, Tar. cuneifoemis, Goes, 1894. K. Svensk. Vet.-Akad. 



Handl., vol. xxv, No. 9, 

 p. 36, pi. vii, figs. 288— 

 290. 

 — WiLLiAMSOtii, Goes, 1894. Ibid., p. 36, pi. vii, figs. 285—287. 



Characters. — Sliell compressed, cuneiform, thickest along the centre. Margins 

 thin, sometimes carinate. Segments numerous, narrow, more or less horizontal ; 

 usually those near the top, but sometimes those nearest the middle, are the longest. 

 Sutures slightly constricted. Texture sub-arenaceous. 



The spathulate, narrow-chambered, thin-edged Te<i;/i/ar?«, which find their best 

 representative form in T. sagittnla, Defrance, constitute the commonest and most 

 widely distributed section of the genus. They seldom attain the dimensions of 

 average specimens of T. gibbosa or T. agglidinans, nor do they usually present 

 so rough an exterior ; but, on the other hand, they are larger and more stoutly 

 built than such forms as T. pygmcea or T. variabilis. 



The contour of the shell is very well described by Prof. Williamson, under the 

 head Textularia cuneiformis, tijirica, who notes the rapid increase in the size of the 

 earlier segments, which imparts to young specimens their triangular form, and 

 the subsequent regularity and evenness in length of the chambers, frequently 

 decreasing rather than increasing in dimensions from the middle of the shell. 

 Sometimes, as in the specimen figured by d'Orbigny from the Canaries, the sutures 

 are limbate. 



PL III, figs. 7 — 9, are ordinary forms with straight chambers and sharp edges. 

 PL V, fig. 15, has widened out more rapidly than usual, and the terminal chamber 

 has grown out of place, with a tendency to linear growth. Fig. 16 has its chambers 

 less symmetrically arranged than in the type-form. Fig. 18 is symmetrical and 

 longer than usual, but slightly flexed, as in many other instances. Fig. 19 will be 

 refen'ed to as var. jugosa (Brady). Fig. 20 is a short, strong, broad variety (sulcata), 

 in which the inner part of each chamber protrudes outward, either close to the median 

 junction (as on one side), or a little way from it (on the other), leaving a depressed 

 channel along the middle of the shell. As it is the upper edge of the chamber (on 

 one side) that thickens to produce this feature, this variety is related to that shown 

 by fig. 19. Fig. 21 is a small specimen, either young or a dwarf form, probably 

 the latter, and is referred to further on (Flabelliformis). 



It may be remarked that Text. Jonesi, Bi^ady, ' Monogr. Carb. Perm. Foram., Pal. 

 Soc.,' 1876, p. 133, pi. X, figs. 20 — 22, are broad, flat, pateozoic forms of 2\ 

 sagittula ; and that T. anceps, Reuss, ' Bohm. Kreid.,' 1846, vol. i, p. 39, pi. viii, fig. 

 78, and pi. xiii, fig. 78 ; and ' Sitz. Ak. Wien,' vol. xl, 1860, p. 234, pi. xiii, fig. 2, is 

 very near to the same species, although its chambers are not horizontal, but somewhat 

 inclined (still more sloping in T. acicxdata and pygmsea). In Terrigi's figs. 24 — 27, 



