the Foraminifera of the Crag. 67 



in the * Annals and Magazine of Natural History ' for June and 

 November 1859; February, March, April, June, July, and 

 November, 1860; August and September 1861 ; February and 

 September 1863. 



These Foraminifera from the Crag at Sutton are remarkable, 

 for the most part, for size and abundance. The leading forms 

 are Miliola, Lagena, Dentalina, Polymorphina, Textularia, Pul- 

 vinulina, and Nonionina. As a fauna, they are best represented 

 (in our collections) by dredgings from the Atlantic, south of the 

 Scilly Isles, at from 50 to 70 fathoms, and from the Mediterra- 

 nean, on the north of Sicily, at 21 fathoms. 



From all other parts of the Lowest or White Crag of Suffolk, 

 as far as our collections serve, we have got a somewhat similar 

 fauna, not only greatly reduced in number of individuals and 

 variety of forms, but composed of dwarfs in contrast with those 

 of Sutton, except in the case of some of those that inhabit shal- 

 low water, as Rotalia Beccarii and Polystomella crispa, and even 

 these are but feeble. Hence we may suppose that the Foramini- 

 feral deposit at Sutton was formed either in deeper or in warmer 

 water than other portions of the Crag were. Our chief sources 

 of these less luxuriant growths are specimens of Crag full of 

 Cyprina and Cardita; and as the former shell lives in the British 

 seas, at from 5 to 80 fathoms — a depth similar to that affected 

 by the Atlantic and Mediterranean groups of Foraminifera above 

 alluded to — we must suppose that some deteriorating influence, 

 either cold currents, floating ice, or cold climate, was at work 

 locally, at least, in the Crag sea, excepting possibly the Sutton 

 area. 



Similar conditions are indicated by the Bivalved Entomostraca 

 of the Crag described in one of the Monographs published by 

 the Palseontographical Society. 



Of the Foraminifera of the Middle or Red Crag we have but 

 a poor supply ; indeed it is not easy to determine in every in- 

 stance whether we have a native, oy a derived fossil in a specimen 

 from the Red Crag, as this deposit has been much disturbed, 

 and with it are mixed fossils from the Lowest or White Crag, 

 and even from older Tertiary beds. (See Mr. S. V. Wood's 

 memoir on this subject, * Quart. Journ. Geol. Soc* 1859, vol. xv, 

 p. 32.) 



The Foraminifei-a of the Red Crag indicate a rather shallow 

 sea-zone; they comprise a few common species oi Miliola, Poly- 

 morphina, Textularia, Truncatulina, Rotalia, Calcarina, Polysto- 

 mella, and Nonionina, not abundant as individuals, nor of large 

 size — and are such as live at present in the British seas, with the 

 exception of Calcarina. 



The Uppermost, Mammaliferous, or Norwich Crag (Thorpe, 



