PRESTWICH FOSSILIFEROUS IRONSANDS, N. DOWNS. 325 



places with blocks fallen from the top of the cliff, and presenting 

 therefore very favourable opportunities for examination, I have not 

 found a single fossil. 



The question was in this state, when, in the month of December 

 1854, Mr. Rupert Jones wrote to me from Charing (near Ashford in 

 Kent), to communicate an interesting fact which he and Mr. Harris 

 had noticed in that neighbourhood. He therein stated, — " The sand- 

 pipes along these hills (from Harrietsham to Charing) abound with 

 fragments of the ferruginous rock of the * basement-bed ' (of the 

 London Clay). This is often a conglomerate, and I recognize the 

 pebbles of this conglomerate as being frequent in the 'pipes.' I 

 observe that it abounds with casts of Pecten, Pectunculus, Calyptraea, 

 &c, but there are none of Melania and Cerithium. We find this 

 iron-rock dispersed among the chalk-flints in the ' pipes,' and also 

 sometimes in the sand-cores of the pipes. There are some large 

 ironstone-fragments in which fossils are absent, but, as other pieces 

 retain but faint graces sometimes, I think that all the pieces may be 

 from the basement-bed." This letter was followed by a considerable 

 collection of the specimens alluded to. In some of the pieces of 

 ironstone the fossils were extremely numerous, but they were all in 

 the state of casts and impressions of species difficult to determine, 

 and of genera common in great part to the Lower Tertiaries ; and as 

 they in fact looked a good deal like the fossiliferous ironstone of the 

 sands under the London Clay at Boughton, near Faversham, my first 

 impression was rather in favour of such a conclusion. Still there were 

 some fossils which did not belong to that period — there were Lunu- 

 lites, a large Terebratula, a species of Emarginula, and some pecu- 

 liar spines of Echini, such as I had never met with in our Lower 

 Tertiary strata ; not being able, however, to form a decided opinion 

 on the subject or to obtain one from any palaeontologist to whom I 

 showed the specimens, I put them on one side waiting further evidence. 

 It was not until Nov. 1855 that I had an opportunity of visiting the 

 spot, and I found Mr. Jones's report quite correct as to these masses 

 of ironstone being in detached blocks in sand-pipes, and mixed up with 

 sandy gravel, clay, and flints. The following is a general section of 

 the hill * :— 



Fig. 2. — Section of Lenham Hill, Kent. 

 a a 

 Lenham. 



The dotted line, y, shows the probable extension of the fossiliferous beds, on the 

 surface of the Chalk, over the hill, and their former extension in the direction of 

 the Weald. 



The blocks of ironstone are found irregularly mixed with sand and 

 gravel in the core of the pipes a, a, the sides of which are lined 



* This section is now much obscured. 



