190 MR. MILLER CHRISTY ON 
In all other directions, the Boulder-clay area extends far beyond 
the Oxlip-Area—southward, south-eastward, eastward, north- 
eastward, and northward. On examination, it will be found that 
the portion of the Boulder-clay area which is covered by the 
Oxlip-Area is not only the most elevated portion but is also the 
most solid portion, being less broken up than any other by 
the narrow strips of gravel and loam which line the bottoms of 
the river-valleys. Very probably, at some past time, the Oxlip 
occupied the greater part, or the whole, of the extensive Boulder- 
clay area of Eastern England; and I shall hereafter give a 
reason which I think goes some way to account for the sub- 
sequent contraction of its Area. 
It should be mentioned that both the outlying localities 
already mentioned (at Dickleburgh and Livermere) are situated 
on Boulder Clay. 
All the places named are shown on the accompanying map. 
VI. Abundance of the Oxlip within its Area. 
Every one has, in spring-time, seen the woods (especially 
those recently cut down) literally “ carpeted” with Primroses. 
Within the region I have defined and have designated the *Oxlip- 
Area," the True Oxlip grows, in all ancient woods, in at least 
equal (if not, as I am inclined to think, in still greater) abundance. 
In many parts of some of the woods within the Area, the plants 
could hardly grow more closely packed together than they do; 
whilst, during the period of flowering (which may be defined as 
from the Jast week in March to the end of April, varying some 
what according to the season), their flowers make the ground 
appear yellow when seen from a short distance. It is true that 
the relative abundance of the plant in different woods within the 
Oxlip-Area varies greatly ; but it may be said, nevertheless, that, 
in England at any rate, it is a striking and characteristic feature 
of the plant that it grows habitually in immense abundance 
wherever it is found. 
The Oxlip, in short, occupies the area in which it grows 3 
completely as the Primrose does the whole of the surrounding 
region and, indeed, the whole of England. Iam not sure whether 
there is any other undoubtedly-indigenous British plant whic 
grows in such enormous abundance over an area so limited 2? 
so sharply defined. 
