WETHERELL — ON NODULAR CONCRETIONS IN FLINTS. 193 



NOTICE OF THE OCCURRENCE IN FLINTS OF SMALL 

 SILICEOUS NODULAR CONCRETIONS, CONTAINING 

 DIFFERENT SPECIES OF FORAMINIFERA. 



By N. T. Wetherell, Esq., M.R.C.S. 



I HAVE often observed in flints from the gravel-pits in the vicinity 

 of Highgate, and at Finchley, Whetstone, and Muswell-hill, small 

 rounded bodies, about the size of a pea. When the flints are fractured, 

 these bodies are generally broken across, and in some instances I have 

 found them to contain Foraminifera.* 



Figs. 1 



3 



Explanation op Figures. 

 Fig. L— Section of a flint with Crjs<p//arm ro/w/^z/ff. a. Specimen not surrounded by a pea-like 

 concretion, b. Specimen surrounded by a nodular body.— "Whetstone gravel-pit. 

 ,, 2.— Portion of a flint with two nodular bodies having hollow centres; the fossils forming the 

 nuclei having disappeared — Muswell-hill. 



,, 3. — Portion of a flint having externally nodular bodies with Foraminifera in their centres. 



Finchley. 



,, 4.— Portion of a flint with a smooth surface, on which is visible a water-worn nodular body 



exposing a Foraminifer in the middle. 

 ,, 5.— Portion of broken flint with numerous sections of minute nodular bodies.— Whetstone. 



As yet, I have only seen one fossil in 

 the centre of each of these small nodules, 

 and I think it is probable that the major 

 part, if not all, of them have an organic 

 centre, although many, when broken, do not 

 exhibit the nucleus. This, I consider, can 

 be explained as follows : — The nodule may 

 be fractured above the centre, as along the line a a', fig. 6 ; or below, 

 as at h V. In either of these cases, the fossil, c, in the centre, which 



Fig. 6. 



* Mr. T. Rupert Jones has, with his usual kindness, given me the names of 

 several of the species — Cristellaria rotulata, Nodosaria zippei, Lituola nautUoidea, 

 L. irregularis, &c. T. W. 



I 



