36 FAMILIAR TREES 



nective," the pollen-sacs splitting longitudinally 

 when the pollen is mature. Then it is that we 

 hear of the "showers of sulphur " which have often 

 terrified the superstitious. This pollen is furnished 

 with the wing-like air-bladders to which we have 

 alluded elsewhere. 



The cones, it is now generally agreed, are more 

 probably inflorescences than flowers, the axis bear- 

 ing scales arranged spirally. We may say either 

 that these scales are produced in pairs, one imme- 

 diately above the other, or that one is borne in 

 the axil of the other. The lower scale in each 

 pair is variously called by botanists of two schools 

 the " bract '' or the " carpel " ; the upper may safely 

 be designated the "ovuliferous scale," though theo- 

 rists deem it either "dwarf shoot" or "placenta." 

 Whilst in the Araucari'nm and Taxodi'nce the 

 two scales in each pair are mainly coalescent, in 

 the Abietince they are distinct. In the Firs and 

 Larches the bract-scale is longer than the ovuli- 

 ferous one ; in the Cedars and Spruces it is rudi- 

 mentary; and in the Pines it soon disappears or 

 coalesces with the ovuliferous scale. Each ovuli- 

 ferous scale in the group bears two ovules in an 

 inverted position, so that the expanded " micropyle," 

 the entrance for the poUen-grain, is between the 

 bases of two contiguous scales of the cone. 



As the cone ripens, the woody ovuliferous scale 

 may either become flat, as in most of the genera ; 

 or it may be thickened at the apex into a rhomboid 

 mass known as the " apophysis," forming the whole 

 of the scale exposed on the surface of the unripe 



