508 H. W. Burrows — Crag Foraminifera. 



have been carefully worked out by Mr. Fortescue W. Millett, of 

 Marazion ; and the lists published by him (1885, 1886, 1894) give 

 a total of 163 species and well-marked varieties. Of this number 

 seventy-six are also met with in the Coralline Crag ; and the 

 additions now made to the rhizopodal fauna of the latter emphasize 

 the similarity to a considerable degree. 



The present notes have special reference to the Crag of the 

 Eastern Counties ; and, although the St. Erth beds are of great 

 interest, they are only thus briefly referred to for the purpose of 

 comparison. They contain a ver}^ rich assemblage of Lagence 

 (thirty-six species) ; while only twenty-three are recorded from the 

 Coralline Crag, of which, however, eighteen are common to the two. 

 One of the most interesting is Lagenn seminuda, Brady, a species 

 met with at only six stations by the " Challenger," two in the South 

 Atlantic and four in the South Pacific, with a range of depth from 

 1300 to 2350 fathoms. In the St. Erth clay it is rare ; but in the 

 Coralline Crag (zone /) it is rather common ; so that we have in 

 the Pliocene beds the earlier appeai'ance of a comparatively shallow- 

 water form, which has apparently since migrated to deeper seas. 

 The PoIymorphincB, so well represented in the Coralline Crag, appear 

 to be somewhat rare at St. Erth ; but of the fifteen recorded species, 

 ten are also found in the former. Taken altogether, the balance of 

 evidence, so far as the Foraminifera are concerned, supports the 

 arguments adduced by Mr. C. Eeid for including the St. Erth beds 

 with the Older Pliocene. 



II. Coralline Crag (termed also the "Suffolk Crag," "White 

 Crag," " Bryozoan or Polyzoan Crag"). — Both by Profo Prestwich 

 (1871), and by Messrs. S. V. Wood, jun., and F. W. Harmer (1872), 

 two main divisions of this Crag were fully recognized. The upper 

 division (zones h and g), 36 feet thick; and lower division (zones 

 / to a), 47 feet, altogether 83 feet, according to Prestwich; and the 

 whole (zones 3'", 3", and 3') 60 feet by the other authors. 



1. At Sutton and Bamsholt zones a, b, c, and part of zone A, are 

 developed. 



The lowest zones were exposed only in long since disused pits. 

 The old pit on Mr. Colchester's farm at Sutton, south side of Sutton 

 Farm Hill, showed in i860 (Prestwich) : Under the surface soil 

 (1 foot) ; zones d and c, 17 feet, the latter rich in Foraminifera; 

 zone h, 4 feet ; zone a, phosphatic nodules, mammalian remains, 

 and foreign boulders (Nodule bed), 1 foot, on London Clay. The 

 Eamsholt pit was correlated with part of zone c. 



2. At Broom Hill ; zones d and c. Pit near the Keeper's Lodge, 

 one mile west of Orford Churcli : Undor the surface soil and drift 

 (3 feet); zone e, 7 feet; d, 15 feet, probably lenticular, not exceeding 

 10 to 12 feet in thickness in 1894. 



Foraminifera are abundant in both zones in this section. In 

 zone d, in addition to the forms common to most of the Coralline 

 Crag exposures, Polystomella crispa is perhaps the most common, 

 together with fine specimens of F. macella. Some of the Poly' 

 morphincB, as P.frondiformis, P. complanata, P.compressa, and P. gibha, 



