FORAMINIFERA OF THE WEST OF SCOTLAND. 271 



269. Discorbina baccata, Heron-Allen & Barland. 



Discorbina baccata, Heron-Allen & Earland, 1913, CI. p. 124, pi. xii. figs. 1-3. 

 4 Stations. 



Very rare. An occasional specimen only, the most typical being at Stn. 7. Since 

 the description of our species was published, we have come across a figure of Terquem 

 (T. 1875, etc., APD. 1881, p. 125, pi. xvi. fig. 1 a-c) of Botalina tnberculata which 

 suggests our species, but both figure and description differ in essential points from our 

 type. Terquem describes his form as smooth, and the figures show no markings except 

 a rosette of beads at the umbilicus and lines radiating from them. I), baccata, on the 

 other hand, has, in perfect specimens, a characteristic rough or " shagreened " (or 

 beaded) surface all over. Of course, Terquem's figure and description may have been 

 based on dead and water-worn shells, and, as his specific name has been appropriated 

 and used for thirty years for a very distinctive type of Balkwill and Wright (B. & W. 

 1885, DIS. p. 350, pi. xiii. figs. 2S-30), it would seem very inadvisable to disturb the 

 nomenclature of the species at this date. Terquem's name (if, indeed, it refers to the 

 same form as our D. baccata) should lapse because of incorrect and insufficient 

 diagnosis. 



270. Discorbina turbo (d'Orbigny). 



Rotalia (Trochulina) turbo, d'Orbigny, 1826, TMC. p. 274. No. 39, Modele No. 73. 

 Discorbina turbo, Brady, 1884, FC. p. 642, pi. lxxxvii. fig. 8 a, b, c. 



14 Stations. 



Generally distributed, but never very abundant. 



271. Discorbina orbicularis (Terquem). 



Rosalina orbicularis, Terquem, 1875, eto., APD. 1876, p. 75, pi. ix. fig. 4. 

 Discorbina orbicularis, Brady, 1884, FC. p. 647, pi. Ixxxviii. figs. 4-8 . 



1 Station. 



Confined to Stn. 15, where it occurred in the free and sessile conditions. 



272. Discorbina mamilla (Williamson). 



Rotalina mamilla, Williamson, 1858, KFGB. p. 54, pi. iv. figs. 109-111. 

 Discorbina mamilla, Heron-Allen & Earland, 1913, CI. p. 123, pi. xi. figs. 4-6. 



20 Stations. 



Almost universally distributed, often very abundant, the best at Stns. 11 and 17. 

 There is hardly any variation in this well-marked form, except in the height of the 

 spire. This is one of the species revived by us for taxonomical purposes (ut supra) ; it 

 has, no doubt, been included by other authors since Williamson's time under the heading 

 of I). rosacea, as it is of frequent occurrence all round the coasts of Britain. 



41* 



