flowers of both species are admirably adapted for cross- 

 fertilisation by the humble-bees which visit them. The 

 stamens first mature, and not until the great part of the 

 pollen is shed does the stigma lengthen and become ready 

 for pollination. The long hairs growing from the stalks 

 which bear the stamens interlock with similar hairs on the 

 inside of the corolla, and thus eifectively prevent the 

 entrance of smaller insects which might visit the flower 

 in search of the abundant honey, but which would fail to 

 effect its fertilisation. The flowers of the species here 

 illustrated are usually a little paler in colour, slightly smaller, 

 and open a little later than those of the Rusty-leaved variety. 

 The plant usually forms a lower and more thickly branched 

 shrub, with rather shorter twigs. But the essential dis- 

 tinguishing features between the two are to be found in 

 their leaves. The leaves of Rhododendron hirsutum are 

 usually broader and less pointed, green underneath, and 

 have well-marked hairs all round their edges. In Rhododendron 

 ferrugineum the leaves tend to be narrower, darker green 

 above, and brown underneath, and are entirely devoid of 

 hairs, but have rolled back edges. Both species are found 

 abundantly in rocky places between 4000 and 8000 feet, 

 and flower in June, July, and August, and may be seen at 

 their best in July. The Rusty-leaved variety seems to 

 prefer a rather moister spot and may also be found on peat. 

 It is most abundant on primary granitic rock, while the other 

 species grows best on limestone. 



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