PrimcBval Man in the Valley of the Lea. 
119 
the “ floor ” above and those found from 20 to 30 ft. beneath 
the surface. The “Palaeolithic Floor” on fig. 8, if present, 
would he just above the horizontal bands of stratification, hut 
the “trail” at this spot has swept it away; it, however, 
occurs in a perfect state a few yards off. Beginning at the 
top, the reference-letter, r, is humus ; q, mud belonging 
to the “trail”; p, a pocket of London-clay; o, “trail”; 
n, Palaeolithic sand and loam crumpled and disturbed by the 
“trail”; m, dark sand and clays; l, light sand and clay; 
k, dark sand and clay; j, yellow sand; i, red sand ; h, light 
sand and clay; g, dark sand and clay; f, red sand; e, yellow 
sand; d, red sand; c, sand, almost white; b, buff sand, some¬ 
times full of the fossil shells of land and fresh-water molluscs. 
These sands represent the sandy margin of the old Thames, 
now four miles distant from this spot. Some of the shells found 
in it by me have been kindly named by Dr. J. Gwyn Jeffreys; 
the series is probably very imperfect, as the time I have for geo¬ 
logical matters is extremely limited; but no doubt the list is 
typical, as I have many times met with the species hereafter 
mentioned; other species may he more rare.or local:— 
1. Corbicula fluminalis, Mull.—Extremely common. 
2. Hydrobia marginata , Mich.—Not uncommon. 
3. Splicerium corneum , Linn. 
4. Pisidium fontinale , Drap.; var. henslowana, Jen. 
5. P. amnicum, Miifl. 
6. XJnio tumulus, Phil. 
7. Bythinia tentaculata, Linn.—Extremely common, with 
abundant free opercula. 
8. Valvata piscinalis , Miifl.; var. subcylindrica. 
9. Planorbis albus, Miifl. 
10. P. complanatus, Linn. 
11. Limncea auricularia , Linn. 
12. L. truncatula, Miifl. 
13. L. peregra, Miifl. 
14. Ancylus Jhiviatilis, Miifl. 
15. Helix concinna, Jeffr. 
16. H. nemoralis, Linn. 
Dr. Jeffreys was good enough to add the following note :— 
“The occurrence of Pisidium fontinale, var. henslowana, as 
well as the tout ensemble of all these fossil shells, induces me 
