392 TREES AND SHRUBS. 



The " male bud " differs from the ordinary buds and the 

 female buds in the fact that it grows at once, in the year 

 it is formed, and produces first a few buds (which next year 

 will become ordinary shoots or else female catkins) and then 

 ends in from two to five male catkins. The cylindrical male 

 catkins, therefore, are visible in late summer, and by Feb- 

 ruary (sometimes after a few fine days in January or even 

 December) they open. 



The drooping male catkin (Fig. 157) has numerous con- 

 cave green scales, each bearing on its downward face (its true 

 upper face) two small scales and a number of stamens (Fig. 

 158) ; each stamen has a short filament ending in a one-lobed 

 anther (a half -anther). There are usually eight of these half- 

 anthers, and (in some cases at least) their filaments are joined 

 in pairs at the base, so that in reality there are only four stamens. 



PERIANTH 

 ...INVOLUCRE' 

 - DRACT 



Fig. 159. Two Female Flowers of Hazel in Axil of a Bract, each with two 

 long Stigmas, and Diagram of same. 



When the female bud opens, a tuft of about twenty scarlet 

 stigmas projects from the top. Carefully dissect the bud 

 and note the brown outer scales, then several pairs of stipules, 

 then a few small leaves, and finally about five bracts each 

 with two female flowers (Fig. 159). The flower consists of 

 an ovary surrounded by a double cup at the base and bearing 

 on top two long red styles, but the lower parts are very small 

 at the time pollination occurs. Only a few flowers in each 

 catkin develop into nuts ; the ovary has two chambers, each 

 with an ovule, but the nut has only one seed. The cup 

 becomes leafy and very conspicuous as the nut ripens. What 

 changes in colour, texture, taste, and size does the nut under- 

 go while ripening? Note the embryo which fills the nut and 

 has two large cotyledons containing starch and oil. Sow 

 ripe nuts, first soaking them in water : do the cotyledons 

 remain below ground or come above it ? 



