Manchester Memoirs, Vol. Hi. (1908), No. IS. 1 1 



Discorbina, Parker and Jones. 



Discorbina turbo, d'Orbi^^ny, sp, (PI. 3, figs, i, 2). 



Rotalia {TrocJmlind) turbo (d'Orb.), Parker, Jones, and 

 Brady ('65^ p. 30, pi. 2, fig. 68. 



The tests are stoutly built, and coarsely perforated 

 both on the superior and inferior surfaces. The sutures 

 are marked by lines of clear shell-substance, varying in 

 width. The height of the spire varies, and the peripheral 

 edge is generally slightly lobulated. If I am right in the 

 diagnosis of these specimens, it is interesting to find them 

 in such comparative abundance ; Discorbina turbo being 

 considered rare in the recent condition. Very frequent. 



*Discorbina globularis, d'Orbigny, sp. and varieties. 

 (PL 3, figs. 3-8, and pi. 4, figs, i, 2.) 



Rosalina variaus, Schultze ('54), p. 60, pi. 3, figs. 8-13. 



R. globularis (d'Orb.), Parker, Jones, and Brady ('65), 

 p. 30, pi. 2, fig. 69. 



R. globularis (d'Orb.), Terquem ('78), p. 25, pi. 2 (7), 

 fig. 10. 



Discorbina globularis (d'Orb.), Brady ('84), p. 643, 

 pi. 86, figs. 8, 13. 



D. globularis (d'Orb.), Brady, Parker, and Jones ('88), 

 p. 226, pi. 46, fig. 6. 



The examples of this common species, shew a very 

 wide range of variation. The type-form is fairly frequent, 

 but the large flat ones similar to Fig. 5, PI. 3 (*), and 

 the rugose ones. Fig. 6, PI. 3 (*), are very common. The 

 rugosity is caused by the growth of the edges of the 

 pores which coalesce, and in some cases this deposit is so 

 thick as to obscure the segmentation of the test. Forms 

 like Fig. 8, PI. 3, and Fig. i, PI. 4 (*), are limbate, and 



