THE ROMANO-BRITISH BARROW ON MERSEA ISLAND. 263 
Mr. Reid remarked that the assemblage is that of plants which 
grow habitually on wet meadow land. One noticeable feature 
of the list is that it includes no cultivated plants. The abundant 
remains of Fumitory and Wild Radish were rather suggestive 
of former cultivation ; but, as both these plants have been found 
fossil in British Pleistocene deposits, their evidence is inconclusive 
on the point. 
Further, I washed out samples, selected from various levels, 
of the grey material which composed the core of the barrow. 
These yielded seeds which appeared to me to represent the 
commonest species in the above list; but, as those seeds actually 
identified gave so little information of interest, these others 
have not been determined in detail. 
The original surface beneath the barrow likewise yielded 
a little moss, and the elytra of beetles. These have not been 
determined ; but, together with a series of the seeds, they have 
been placed in the keeping of the Essex Museum of Natural 
Histroy at Stratford. 
(3.) GEOLOGICAL OBSERVATIONS .—I submitted five 
samples of the material of which the barrow was built to Mr. 
G. M. Davies, F.G.S., of the Imperial Institute, South Kensing¬ 
ton, and I am indebted to him for the following report upon 
them :— 
(1.) Ironstone at 10ft. 6 in. from top of mound. 
Two pieces of coarse sand and earth cemented by hydrated oxide 
of iron. A film of black or dark red limonite is generally visible near 
the centre of the slab, and the degree of cementation diminishes above 
and below this, giving a fairly-compact slab about f inch thick. 
The less-ferruginous outer portions can be crumbled and washed 
clear in water, the binding material being little more than ochreous clay. 
A clean quartz-sand results, with a little flint in the form of pebbles and 
splinters. Small pieces of black coaly matter are present, probably 
charcoal. On heating, the ironstone produces an “ organic ” smell, and 
results in reduction to magnetic oxide of iron. 
The heavy minerals in the washed sand, apart from abundant spheroidal 
concretions of impure limonite, are ilmenite, garnet, zircon, tourmaline, 
rutile, staurolite, hornblende, epidote, kyanite, and andalusite. 
(2.) Grey Material at 11 feet. 
Grey loamy sand with flint pebbles. Two fragments of red chert 
were also noted. Under the microscope these appear rather coarse in 
texture, with cylindrical inclusions of iron oxide. These appear to repre¬ 
sent sponge spicules, one example in particular resembling part of a 
tetractinelled spicule. Small fragments of charcoal and numerous rootlets 
