THE PINE AND OTHER CONIFERS. 293 



easily overlooked. They consist of a quantity of 

 double scales arranged in a spiral. The double 

 scale consists of an upper part which later on usually 

 becomes woody and much expanded, and of a lower 

 membranous part, both of which are especially easily 

 seen in the cone of the Douglas Fir {Pimcs nobilis). 

 The exact nature of these two scales is by no means 

 certain. Generally the upper one is supposed to be 

 a female flower, consisting of a flat axis which bears 

 the two ovules, whilst the lower one is its bract. 

 Some writers have suggested that the upper ovule-scale 

 is really the two edges of the lower one, which have 

 been doubled over (see Worsdell). 



The two ovules are quite exposed on the upper 

 surface of the scale and near the axis. There is 

 therefore no closed ovary, as in the higher plants. 

 But the ovules are not so liable to injury as 

 one might expect, for they are exposed only for 

 a very short time. The pollen, after being blown 

 to the ovule, is drawn down into the latter by a 

 special mucilage secreted by it. Very soon after this, 

 the cone is closed up by the growth of the scales 

 and by the secretion of resin, so that the entire cone 

 becomes a hard resinous body which is quite impervious. 

 Even the nutcracker, a bird which is exceedingly fond 

 of pineseeds, cannot break open the cone or touch the 

 seeds until the scales open of themselves later on to 

 allow the seeds to escape. 



The scales remain sealed together for two years, 

 during which they grow to the mature size, and 

 the seeds gradually develop. Eventually they open, 

 generally in the afternoon, and in windy, dry weather. 

 The seeds, by this time fully ripe, are beautifully 

 fitted to catch the wind. They have a long, thin 



