Manchester Memoirs, Vol. Ixii. (19 17) 113 



274. DlSCORBINA OPERCULARIS, var. ELEGANS, nOV. 



PL VII, fig. 2 



This variety differs from the type in its invariably smaller 

 dimensions, neater build, broader and less arched chambers, 

 and the lesser and more gradually increasing widtE of its spiral 

 whorls. The drawing given here represents well the character- 

 istics described above. Diam. .3 mm. 



The variety is rare and not always accompanied by its type 

 species. 



(The variety would not appear to be worth separating. It 

 probably only represents a depauperate form of the type exist- 

 ing under unfavourable conditions.) 



275. Discorbina pileolus, (d'Orbigny.) 



Valvulina pileolus, d'Orbigny, 1839, Voyage Amer. Merid., 

 vol. V, pt. s, "Foraminiferes," p. 47, pi. I, figs. 15-17. 



Discorbina pileolus, Brady, 1884, Chall. Rep., vol. IX, p. 649, 

 pi. LXXXIX, figs. 2-4. 



Very rare; two small specimens found in the lowest soft 

 beds of the Marl. 



276. Discorbina concinna, Brady. 



Discorbina concinna, Brady, 1884, Chall. Rep., vol. IX, p. 646, 

 pi. XC, figs. 7-8. 



Very rare, only two small specimens noted. 



277. Discorbina rosacea, (d'Orbigny.) 



Rotalia rosacea, d'Orbigny, 1826, Ann. Sci. Nat., vol. VII, p. 



273, No. 15. 

 Discorbina rosacea, Brady, 1884, Chall. Rep., vol. IX, p. 644, 



pi. LXXXVII, figs. 1, 4. 



Rare and small. 



278. Discorbina orbicularis, (Terquem.) 



Rosalina orbicularis, Terquem, 1876, Ess. Anim. Plage Dun- 



kerque, pt. 2, p. 75, pi. IX, fig. 4a. b. 

 Discorbina orbicularis, Brady, 1884, Chall. Rep., vol, IX, p. 



647, pi. LXXXVIII, figs. 4-8. 



Less rare than the last species but still not frequent. 



