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approach to cleistogamy doubtless harmonizes well with the 
conditions of life under which these Arctic plants live. On the 
other hand it is then of but slight biological importance that 
the corollas are coloured and doubtless on the whole keep fresh 
a very long time. (On this and on Cleistogamy in Campanula 
uniflora see Warmine, 1886, b, pp. 150—154.) 
Of other peculiarities it is interesting to note the examples 
of the ovary being protected by a similar covering of hairs as 
are the vegetative parts, while the style is quite glabrous; here 
again it is two of the open-flowering species, Ledum and 
Rhododendron, which must be mentioned; of the others Phyl- 
lodoce only (and Erica Tetralix). 
Vaccinium- and Arctostaphylos-species have fleshy fruits; 
the others have capsules. As examples of plants in which the 
stalk of a drooping flower rises straight into the air when 
the fruit becomes a capsule may be mentioned Casszope and 
Phyllodoce. In the nodding capsule in Ledum the position of 
the valves is in harmony with this position of the fruit. 
In all the species the flowers are undoubtedly formed the 
year previous to that in which they open; this has at any rate 
been verified in the greater number of them. They are most 
developed in Arctostaphylos alpina which is also the one to 
flower the earliest in spring. Considering the shortness of the 
summer it is evidently very useful that the development of 
the flowers should be spread over two years. 
All the Greenland Ericacee have woody stems and should 
be referred to the growth-form called ‘‘dwarf-sbrubs” (some 
are of decided prostrate growth, e. g. Arctostaphylos alpina and 
A. Uva-ursi); Pirola however differs most in this respect. 
The buds have typical scale-leaves in most of the species 
(Arctostaphylos, Andromeda, Cassandra, Ledum, Vaccinium, etc.) ; 
quite devoid of scale-leaves are Cassiope tetragona, the Arctic 
heather which extends farthest towards the north, and Casszope 
