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H. Hamshaw Thomas. 
which find their way into the joints and cracks where a small 
amount of humus may have collected. When a little humus has 
collected on the rock, Galium veruni and Thymus Serpyllum are 
abundant, the latter showing its creeping tufted habit. A variety 
of other plants occur, e.g., Saxifraga tridactylites, Cerastium spp., 
many species of Hicracium, Aquilega vulgaris with flowers of 
various shades of purple and blue. Geranium robertianum and 
Pastinaca sativa occur plentifully in the open vegetation of rock 
places. 
Other Associations. 
Near Visby much of the surface above the cliffs has been at 
one time quarried for stone ; in many places considerable areas 
are covered with rubbly material with some patches of bare rock 
and some patches of shallow turf. The quarrying operations 
probably ceased more than four centuries ago so that the vegetation 
here may be considered as fairly natural. From somewhat casual 
inspection it would appear that these tracts were colonised, first by 
mosses and Scdum, followed by Thymus and Galium: then many 
isolated plants of Hieracium, Aquilegia, Geranium, etc., appear, 
together with large quantities of Cynanchum vincetoxicum, an 
interesting Asclepiadaceous plant. This plant has woody stems 
about a foothigh and dark green leaves. With it, and where there 
is more soil between the stones, we get a considerable growth of 
low shrubby bushes, many of them procumbent. The following 
are common :— 
Primus spinosa. 
Cratcegus monogyna ? 
Juniperus communis. 
Cotoneaster inteseerrima. 
Berberis vulgaris. 
Arctostaphylos Uva-ursi. 
Rosa, spp. 
Sorbus fennica. 
Where the ground has been undisturbed and a thin layer of 
soil covers the rock there is a vegetation of the limestone pasture 
type, containing various Grasses and Hieracia with 
Anthyllis vulneraria. 
Asperula tinctoria. 
Pulsatilla patens. 
Poterium Sanguisorba. 
Helianthemum Fumaria. 
Geranium spp. 
Ononis repens. 
Cnicus acaulis. 
Cerastium glutinosum. 
Allium Schoenopersum. 
1 This species was in fruit and in most cases the seeds appeared 
to be sprouting while still attached to the capsule. Some of 
the seedlings were 2 to 3 cms. long in spite of the dryness of 
the weather. 
